


















































































































































United States 
Environmental Protection 
Ml M % Agency 


EcoMat Inc.'s Biological 
Denitrification Process 


Innovative Technology 
Evaluation Report 

























































EPA/540/R-01/501 
May 2002 


EcoMat Inc.’s Biological 
Denitrification Process 

Innovative Technology Evaluation Report 



National Risk Management Research Laboratory 
Office of Research and Development 
U.S. Environmental Protection Agency 
Cincinnati, Ohio 45268 



Recycled Recyclable 

Printed with vegetable-based ink or 
paper that contains a minimum ot 
50 a ? post-consumer fiber content 
processed chlorine free 


Notice 


The information in this document has been funded by the U.S. Environmental Protection Agency 
(EPA) under Contract Nos. 68-C5-0036 and 68-C00-179 to Science Applications International 
Corporation (SAIC). It has been subjected to the Agency’s peer and administrative reviews and has 
been approved for publication asan EPA document. Mention oftrade names or commercial products 
does not constitute an endorsement or recommendation for use. 





Foreword 


The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation’s land, 
air, and water resources. Under a mandate of national environmental laws, the Agency strives to 
formulate and implement actions leading to a compatible balance between human activities and the 
ability of natural systems to support and nurture life. To meet this mandate, EPA’s research program 
is providing data and technical support for solving environmental problems today and building a 
science knowledge base necessary to manage our ecological resources wisely, understand how 
pollutants affect our health, and prevent or reduce environmental risks in the future. 

The National Risk Management Research Laboratory (NRMRL) is the Agency’s center for 
investigation of technological and management approaches for preventing and reducing risks from 
pollution that threatens human health and the environment. The focus ofthe Laboratory’s research 
program is on methods and their cost-effectiveness forprevention and control of pollution to air, land, 
water, and subsurface resources; protection of water quality in public water systems; remediation of 
contaminated sites, sediments and ground water; prevention and control of indoor air pollution; and 
restoration of ecosystems. NRMRL collaborates with both public and private sector partners to foster 
technologies that reduce the cost of compliance and to anticipate emerging problems. NRMRL’s 
research provides solutions to environmental problems by; developing and promoting technologies 
that protect and improve the environment; advancing scientific and engineering information to support 
regulatory and policy decisions; and providing the technical support and information transfer to ensure 
implementation of environmental regulations and strategies at the national, state, and community 
levels. 

This publication has been produced as part of the Laboratory’s strategic long-term research plan. It 
is published and made available by EPA’s Office of Research and Development to assist the user 
community and to link researchers with their clients. 


Hugh W. McKinnon, Director 

National Risk Management Research Laboratory 



Abstract 


This report summarizes the findings of an evaluation of a biodenitrification (BDN) system developed 
by EcoMat Inc. of Hayward, California (EcoMat). This evaluation was conducted between May and 
December of 1999 under the U.S. Environmental Protection Agency Superfund Innovative 
Technology Evaluation (SITE) Program; it was conducted in cooperation with the Kansas Department 
of Health and Environment (KDHE). The demonstration site was the location of a former public water 
supply well in Bendena, Kansas. The well water is contaminated with high levels of nitrate. Based on 
historical data, nitrate concentrations in the water have ranged from approximately 20 to 130 ppm, 
well above the regulatory limit of 10 mg/I. Low concentrations of volatile organic compounds (VOCs), 
particularly carbon tetrachloride (CCI 4 ), have been a secondary problem. The overall goal of EcoMat 
was to demonstrate the ability of its process to reduce the levels of nitrate in the groundwater to an 
acceptable concentration, thus restoring the water supply well as a drinking water source. 

EcoMat's process is a two component process consisting of 1) an ex situ anoxic biofilter BDN system, 
and 2) a post-treatment system. The BDN system utilizes specific biocarriers and bacteria to treat 
nitrate-contaminated water, and employs a patented reactorfor mixing the suspended biocarriers and 
retaining biocarrier within the reactors to minimize solids carryover. Methanol is added to the system 
as a carbon source for cell growth and for inducing metabolic processes that remove free oxygen 
and encourages the bacteria to consume nitrate. EcoMat’s post-treatment system can be subdivided 
into two primary treatment parts: one part for oxidation and a second part forfiltration. The oxidation 
treatment is intended to oxidize residual nitrite back to nitrate, oxidize any residual methanol, and 
destroy bacterial matter exiting the BDN system. The oxidation treatment may consist of ozonation 
or ultraviolet (UV) treatment, or a combination of both. Filtration usually consists of a clarifying tank 
and one or more filters designed to remove suspended solids generated from the BDN process. 

The demonstration consisted of four separate sampling events interspersed over a 7!4 month period 
of time. During these events EcoMat operated its system to flow between three and eight gallons per 
minute. During this same time period nitrate levels in the well water varied from greaterthan 70 mg/I 
to approximately 30 mg/I. ForEvent 1, chlorination was the only post-treatment used. Post-treatment 
for Event 2 consisted of clarification; sand filtration; cartridge filtration using 20pm rough filters; and 
UV oxidation. Post-treatment for Event 3 consisted of ozone; UV oxidation; clarification; cartridge 
filtration using 20pm rough filters, 5pm high efficiency filters, carbon adsorption, and 1 pm polishing 
filters. Post-treatmentforEvent4 consisted of chlorination, clarification, 5pm high efficiency filtration, 
airstripping, and 1pm polishing filtration. 

The primary objective of the study focused on three performance estimates. The first performance 
estimate was to determine if the BDN portion of the process was capable of reducing combined 
nitrate-N/nitrite-N (total-N) to less than 10.5 mg/I. The second performance estimate included 
evaluation of the post-treatment for its ability to produce treated groundwater that would meet 
applicable drinking water standards with respect to nitrate-N, nitrite-N, and total-N, using a level of 
significance of 0.10. This required reducing high levels ofnitrate-N to less than 10.5 mg/I, maintaining 
nitrite-N levels to less than 1.5 mg/I, and achieving a total-N level of less than 10.5 mg/I. When 
rounded to whole numbers, these performance estimates would meet the regulatory maximum 
contaminant limits (MCLs) of 10, 1, and 10 mg/I for nitrate-N, nitrite-N, and total-N respectively. The 


IV 



Abstract (Cont’d) 


third performance estimate involved evaluating the final effluents for other parameters, such as 
turbidity, pH, residual methanol, suspended solids, and biological material. 

Results for the final system outfall indicate that when the post BDN effluent contains nitrite-N levels 
in excess of the regulatory limit of 1 mg/I the EcoMat post-treatment components failed to adequately 
and reliably reduce the nitrite-N levels to below the 1 mg/I level. The post-treatment system was 
varied considerably throughout the demonstration. For Event 1, chlorination was the only post¬ 
treatment used. Post-treatment for Event 2 consisted of clarification; sand filtration; cartridge filtration 
using 20pm rough filters; and UV oxidation. Post-treatment for Event 3 consisted of ozone; UV 
oxidation; clarification; cartridge filtration using 20pm rough filters, 5pm high efficiency filters, carbon 
adsorption, and 1pm polishing filters. Post-treatment for Event 4 consisted of chlorination, 
clarification, 5pm high efficiency filtration, air stripping, and 1 pm polishing filtration. Comparison of 
samples collected immediately upstream and immediately downstream of the post-treatment systems 
indicated that none of the combinations used were effective for removing residual methanol. In all 
instances methanol levels were virtually the same orhigherin finaleffluentexiting the post-treatment 
systems. 

Since the post-treatment system implemented by EcoMat varied foreach of the fourevents, data from 
the four events was first analyzed separately. Formal statistical analyses were used to address the 
first two performance estimates discussed above, using a significance level of 0.10. The overall 
conclusion from these tests was that: 

• Events 1 and 2 were found to be successful in meeting the first two performance goals for 
significantly reducing levels of nitrate-N and nitrite-N after BDN and after post treatment. 

• Event 3 and 4 were not shown to be successful in significantly reducing levels of nitrate-N 
and nitrite-N after BDN and after post treatment. 

Daily dissolved oxygen (DO) field measurements indicated that the de-oxygenating step of EcoMat’s 
BDN process may not have been optimized throughout the demonstration, and especially during 
Events 3 and 4. The desired DO level of partially biodenitrified (partial BDN) water in the De- 
oxygenating Tank is < 1 mg/I. However, DO values below 1 mg/I were measured only during the first 
two events. 

The effectiveness of the post-treatment systems were variable for different parameters. Comparison 
of samples collected immediately upstream and immediately downstream of the post-treatment 
systems indicated that none of the combinations used were effective for removing residual methanol 
to the demonstration objective of < 1 mg/I. In all instances, downstream methanol levels were virtually 
the same or higher than upstream methanol levels. Methanol concentrations averages in final effluent 
were between 15 and 98 mg/I during the four events, the first two events appear to have had a 
substantial beneficial impact on solids carryover. Residual bacterial content in the final effluent, 
decreased significantly in Events 3 and 4, likely the result of adding “high efficiency" (5pm) and 
“polishing" (1pm) filters to the post-treatment system. Nevertheless, the levels of total heterotrophic 
and facultative anaerobe bacterial matter measured in the final effluent for all events was well above 
corresponding inlet water levels. 

An economic analysis was also conducted for estimating the cost of implementing EcoMat’s biological 
denitrification technology at full-scale. For a 100 gpm system, the estimated cost to treat nitrate- 
contaminated groundwater over a one year period is $490,000, or approximately $0.012/gal. The 
cost over 5, 10,or 15 years is estimated to increase to approximately$730,000 ($0.0034/gal.); 
$1,000,000 ($0.0024/gal.) and $1,300,000 ($0.002/gal.), respectively. 


v 



Contents 


Notice. ii 

Foreword .iii 

Abstract . iv 

Tables. ix 

Figures. xi 

Abbreviations and Acronyms .xii 

Acknowledgments .xiv 

Executive Summary ..ES-1 

1.0 Introduction .1 

1.1 Background .1 

1.2 Brief Description of the SITE Program.2 

1.3 The SITE Demonstration Program and Reports .2 

1.4 Purpose of the Innovative Technology Evaluation Report (ITER) .2 

1.5 Technology Description .3 

1.6 Key Contacts . . .'.4 

2.0 Technology Applications Analysis.5 

2.1 Key Features of the BDN and Post-Treatment Processes.5 

2.2 Operability of the Technology.6 

2.3 Applicable Wastes .7 

2.4 Availability and Transportability of Equipment.7 

2.5 Materials Handling Requirements .8 

2.6 Range of Suitable Site Characteristics. 8 

2.7 Limitations of the Technology.9 

2.8 ARARS for the EcoMat BDN Technology .10 

2.8.1 Comprehensive Environmental Response, Compensation, and 

Liability Act (CERCLA).10 

2.8.2 Resource Conservation and Recovery Act (RCRA).12 

2.8.3 Clean Air Act (CAA).12 

2.8.4 Clean Water Act (CWA) .12 

2.8.5 Safe Drinking Water Act (SDWA) .13 

2.8.6 Occupational Safety and Health Administration (OSHA) 

Requirements . 13 

3.0 Economic Analysis . 15 

3.1 Introduction. 15 

3.2 Conclusions . 19 

3.3 Factors Affecting Estimated Cost. 19 

3.4 Issues and Assumptions . 19 


VI 







































Contents (Cont’d) 


3.4.1 Site Characteristics.19 

3.4.2 Design and Performance Factors.19 

3.4.3 Financial Assumptions ..20 

3.5 Basis for Economic Analysis .20 

3.5.1 Site Preparation.20 

3.5.2 Permitting and Regulatory Requirements.21 

3.5.3 Capital Equipment.21 

3.5.4 Startup and Fixed Costs ..22 

3.5.5 Labor..'.22 

3.5.6 Consumables and Supplies.23 

3.5.7 Utilities.24 

3.5.8 Effluent Treatment and Disposal.25 

3.5.9 Residuals Shipping and Disposal.25 

3.5.10 Analytical Services .25 

3.5.11 Maintenance and Modifications.25 

3.5.12 Demobilization.26 

4.0 Demonstration Results .27 

4.1 Introduction. 27 

4.1.1 Project Background.27 

4.1.2 Project Objectives.27 

4.2 Detailed Process Description.27 

4.2.1 BDN System .28 

4.2.2 Post-Treatment System . 31 

4.3 Field Activities .31 

4.3.1 Pre-Demonstration Activities.31 

4.3.2 Sample Collection and Analysis .32 

4.3.3 Process Monitoring.32 

4.3.4 Process Residuals .32 

4.4 Performance and Data Evaluation.34 

4.4.1 Event 1 .34 

4.4.2 Event 2 .45 

4.4.3 Event 3 . . . ..54 

4.4.4 Event 4 .65 

4.4.5 Inter-Event Comparison .74 

4.4.6 Data Quality Assurance .76 

5.0 Other Technology Requirements .80 

5.1 Environmental Regulation Requirements.80 

5.2 Personnel Issues.80 

5.3 Community Acceptance.80 

6.0 Technology Status. 81 


vii 











































Contents (Cont’d) 


6.1 Previous Experience .81 

6.2 Ability to Scale Up .81 

7.0 References .82 

Appendix A - Developer Claims and Discussion .A-1 


viii 







Tables 


Table_Page 

2- 1 Federal and State ARARS for the EcoMat BDN Process.11 

3- 1 Cost Estimates for Initial YearoflOOGPM BDN System, Online 80%.16 

3- 2 Cost Estimates for EcoMat’s BDN System for Multi-Year Treatment Scenarios .17 

4- 1 Demonstration Objectives.29 

4-2 Summary of Laboratory Analyses Conducted for the Demonstration.33 

4-3 Summary of Field Measurements Conducted for the Demonstration.33 

4-4 Event 1 - Summary Statistics .36 

4-5 Event 1 - Nitrate-N and Nitrite-N Results .37 

4-6 Event 1 - Summary of Treatment Effectiveness .38 

4-7 Event 1 - Dissolved Oxygen Measurements.39 

4-8 Event 1 - pH Measurements . 39 

4-9 Event 1 - Turbidity Measurements .40 

4-10 Event 1 - TSS Results.41 

4-11 Event 1 - Microbial Results (TCH, FA, and FC) .42 

4-12 Event 1 - Methanol Results .43 

4-13 Event 1 - Supplemental Analyses Results .43 

4-14 Event 2 - Summary Statistics .46 

4-15 Event 2 - Nitrate-N and Nitrite-N Results .47 

4-16 Event 2 - Summary of Treatment Effectiveness .48 

4-17 Event 2 - Dissolved Oxygen Measurements.49 

4-18 Event 2 - pH Measurements .49 

4-19 Event 2 - Turbidity Measurements .50 

4-20 Event 2 - TSS Results.50 

4-21 Event 2 - Microbial Results (TCH, FA, and FC) .51 

4-22 Event 2 - Methanol Results.52 

4-23 Event 2 - Supplemental Analyses Results .53 

4-24 Event 3 - Summary Statistics .55 

4-25 Event 3 - Nitrate-N and Nitrite-N Results .56 

4-26 Event 3 - Summary of Treatment Effectiveness .58 

4-27 Event 3 - Dissolved Oxygen Measurements.59 

4-28 Event 3 - pH Measurements . 59 

4-29 Event 3 - Turbidity Measurements .60 

4-30 Event 3 - TSS Results.60 

4-31 Event 3 - Microbial Results (TCH, FA, and FC) .61 

4-32 Event 3 - Methanol Results. 62 

4-33 Event 3 - Supplemental Analyses Results .63 


IX 








































Tables (Cont’d) 


4-34 Event 4 - Summary Statistics .66 

4-35 Event 4 - Nitrate-N and Nitrite-N Results .67 

4-36 Event 4 - Summary of Treatment Effectiveness .68 

4-37 Event 4 - Dissolved Oxygen Measurements.69 

4-38 Event 4 - pH Measurements .69 

4-39 Event 4 - Turbidity Measurements .70 

4-40 Event 4 - TSS Results.70 

4-41 Event 4 - Microbial Results (TCH, FA, and FC) .72 

4-42 Event 4 - Methanol Results.73 

4-43 Event 4 - Supplemental Analyses Results .73 

4-44 Inter-Event Comparison of Demonstration Criteria for Final Effluent .76 

4-45 Nitrate Matrix Spike Percent Recovery Summary.78 

4-46 Nitrite Matrix Spike Percent Recovery Summary .78 

4-47 Nitrate MS/MSD Relative Percent Difference Summary.78 

4-48 Nitrite MS/MSD Relative Percent Difference Summary .78 

4-49 Nitrate Field Duplicate Summary.79 

4-50 Nitrite Field Duplicate Summary .79 


x 




















Figures 


Figure_Page 

3- 1 Cost Distributions - EcoMat Biodenitrification Multi-Year Treatment Scenarios.18 

4- 1 Flow Diagram Showing EcoMat’s Treatment System and Sample Collection Points ... 28 

4-2 Detailed Schematic of the EcoMat Denitrification Reactor.30 

4-3 Event 1 - Treatment Effectiveness for Averaged Test Results .35 

4-4 Event 1 - Comparison of Flow Rate Fluctuation and Final Effluent Total-N 

Concentrations .44 

4-5 Event 2 - Treatment Effectiveness for Averaged Test Results .45 

4-6 Event 2 - Comparison of Flow Rate Fluctuation and Final Effluent Total-N 

Concentrations .54 

4-7 Event 3 - Treatment Effectiveness for Averaged Test Results .55 

4-8 Event 3 - Comparison of Flow Rate Fluctuation and Final Effluent Total-N 

Concentrations .64 

4-9 Event 4 - Treatment Effectiveness for Averaged Test Results .65 

4-10 Event 4 - Comparison of Flow Rate Fluctuation and Final Effluent Total-N 

Concentrations .74 

4-11 Inter-Event Comparison - Treatment Effectiveness for Nitrate-N/Nitrite-N .75 


XI 















Abbreviations and Acronyms 


AQCR 

AQMD 

ATTIC 

ARARs 

BDN 

^3 

cm 

CAA 

CCI 4 

CERI 

CERCLA 

CFR 

CSCT 

cfu 

CWA 

Dl 

DO 

EcoMat 

EDA 

FA 

FC 

FS 

FID 

ft 2 

gpm 

GC/MS 

G&A 

g/cm 3 

HSWA 

ICP 

ITER 

KDHE 

kW/Hr 

LDR 

LOS 

_ 3 

m 

MS/MSD 

MCLs 

MCLGs 

MDL 

MeOH 

mg/I 


Air Quality Control Regions 

Air Quality Management District 

Alternative Treatment Technology Information Center 

Applicable or Relevant and Appropriate Requirements 

Biodenitrification 

Cubic centimeter 

Clean Air Act 

Carbon tetrachloride 

Center for Environmental Research Information 

Comprehensive Environmental Response, Compensation, and Liability Act 

Code of Federal Regulations 

Consortium for Site Characterization Technologies 

Colony forming units 

Clean Water Act 

Deionized 

Dissolved oxygen 

EcoMat Inc. of Hayward, CA 

Exploratory data analysis 

Facultative anaerobes 

Fecal coliform 

Feasibility study 

Flame Ionization Detector 

Square feet 
Gallons per minute 

Gas chromatography/mass spectroscopy 

General and administrative 

Gram per cubic centimeter 

Hazardous and Solid Waste Amendments 

Inductively coupled plasma spectroscopy 

Innovative Technology Evaluation Report 

Kansas Department of Health and Environment 

Kilowatts per hour 

Land disposal restriction 

Level of significance 

Cubic meter 

Matrix spike/matrix spike duplicate 
Maximum contaminant levels 
Maximum contaminant level goals 
Method detection limit 
Methanol or methyl alcohol 
Milligrams per liter 


XII 



Abbreviations and Acronyms (Cont’d) 


MPN 

NAAQS 

NCP 

NIST 

NOAA 

NPDES 

NPL 

NRMRL 

NSCEP 

Nitrate-N 

Nitrite-N 

ND 

NPDWS 

NTU 

OSHA 

ORD 

OSWER 

OSC 

PLFA 

POTW 

PPE 

PQL 

POA 

PVC 

PWS 

POTW 

QAPP 

RPD 

RI/FS 

RPM 

RCRA 

SAIC 

SARA 

SDWA 

SOP 

SW-846 

SWDA 

SITE 

S.U. 

TER 

TCH 

TOC 

TSCA 

TSD 

THM 

pg/i 

uv 

US EPA 

VOC 

WSR 


Most probable number 

National Ambient Air Quality Standards 

National Oil and Hazardous Substances Pollution Contingency Plan 
National Institutes of Standards and Technology 
National Oceanographic and Aeronautic Administration 
National Pollutant Discharge Elimination System 
National Priorities List 

National Risk Management Research Laboratory (EPA) 

National Service Center for Environmental Publications 

A measure of nitrate in which each mg/I of nitrate-N equates to 4.4 mg/I of nitrate 
A measure of nitrite in which each mg/I of nitrite-N equates to 3.2 mg/I of nitrite 
Non-detectable, not detected, less than detection limit 
National primary drinking water standards 
Normal turbidity unit 

Occupational Safety and Health Administration 
Office of Research and Development (EPA) 

Office of Solid Waste and Emergency Response (EPA) 

On-scene coordinator 

Phospholipid fatty acids 

Publicly owned treatment works 

Personal protective equipment 

Practical quantitation limit 

Project Objective Agreement 

Polyvinyl chloride 

Public water supply 

Publicly owned treatment works 

Quality assurance project plan 

Relative percent difference 

Remedial Investigation / Feasibility Study 

Remedial project manager 

Resource Conservation and Recovery Act 

Science Applications International Corporation 

Superfund Amendments and Reauthorization Act 

Safe Drinking Water Act 

Standard operating procedure 

Test methods for evaluating solid waste, physical/chemical methods 

Solid Waste Disposal Act 

Superfund Innovative Technology Evaluation 

Standard units 

Technology Evaluation Report 
Total culturable heterotrophs 
Total organic carbon 
Toxic Substances Control Act 
Treatment, storage, and disposal 
Trihalomethanes 
Micrograms per liter 
Ultraviolet 

United States Environmental Protection Agency 
Volatile organic compound 
Wilcoxon signed rank 


xiii 



Acknowledgments 


This reportwas prepared underthe direction of Dr. Ronald Lewis (retired) and Mr. Randy Parker, the 
EPA Technical Project Managers for this SITE demonstration at the National Risk Management 
Research Laboratory (NRMRL) in Cincinnati, Ohio. EPA NRMRL peer review of this report was 
conducted by Mr. Vicente Gallardo. Mr. Andrew Matuson of Science Applications International 
Corporation (SAIC) served as the SITE work assignment manager for the implementation of 
demonstration field activities and completion of all associated reports. 

The demonstration required the combined services of several individuals from EcoMat Inc., the 
Kansas Departmentof Health Services (KDHE), the town of Bendena, KS, and SAIC. PeterHalland 
Jerry Shapiro of EcoMat, Inc. served as logistical and technicalcontacts forthe developer. Rick Bean 
of the KDHE was instrumental for making provisions for the treatment shed and associated utilities, 
and forconducting additionalsampling and analysis independent ofthe SITE Program. Iraj Pourmirza 
of the KDHE Bureau of Water - Water Supply Section provided technical support regarding drinking 
water issues. The cooperation and efforts of these organizations and individuals are gratefully 
acknowledged. 

This reportwas prepared by Joseph Tillman, Susan Blackburn, Craig Chomiak, and John Nicklas, 
of SAIC. Mr. Nicklas also served as the SAIC QA coordinator for data review and validation. Joseph 
Evans (the SAIC QA Manager), Dr. Herbert Skovronek, and James Rawe, all of SAIC, internally 
reviewed the report. Field sampling and data acquisition was conducted by William Carrier, Dan Patel, 
Steve Stavrou, and Joseph Tillman. 


Cover Photographs: Clockwise from top left are 1) “EcoLink" - synthetic polyurethane cubes, 1 cm on a side, 
used as biocarrier medium; 2) Gas detector tube monitoring above overflow tank (dark tank in background is 
the “EcoMat Reactor", also known as “R2"); 3) Concrete cap for 23 ft. ID Public Water Supply Well # 1 (vent 
pipe visible on right side of cap); 4) Post-BDN effluent discharging to overflow tank; 5) Overview of 
biodenitrification system - Overflow tank (front), 2 m 3 EcoMat Reactor (center), and De-oxygenating Tank (far 
right); 6) Portion of post-treatment system (clarifying tank at left); and 7) Shed for housing treatment system. 


XIV 



Executive Summary 


This reportsummarizes the findings of an evaluation of the 
EcoMat Biodenitrification (BDN) treatment process. The 
process was tested fortreating groundwater contaminated 
with high levels of nitrate at the location of a former public 
water supply well in Bendena, Kansas. This evaluation 
was conducted under the U.S. Environmental Protection 
Agency (EPA) Superfund Innovative Technology 
Evaluation (SITE) Program. 

It should be noted that BDN processes have been used for 
some years for treatment of wastewater and groundwater. 
However, the technology has been known in the past to be 
applied to the treatment of groundwater for drinking water 
purposes. Thus, the SITE Program’s interest was to 
evaluate such an application. 

Overview of Site Demonstration 

The EcoMat BDN process is a type of fixed film 
bioremediation that uses specific biocarriers and bacteria 
to treat nitrate-contaminated water. Fixed film treatment 
allows rapid and compact treatment of nitrate with minimal 
byproducts. Unique to the EcoMat system is a patented 
mixed reactor that retains the biocarrier within the system, 
thus minimizing solids carryover. Methanol is added to the 
system as a source of carbon for cell growth and for 
inducing metabolic processes thatremove free oxygen and 
encourage the bacteria to consume nitrate. Methanol is 
also important to assure that the nitrate conversion results 
in the production of nitrogen gas rather than the 
intermediate nitrite, which is considered to be more toxic. 

EcoMat’s BDN system was evaluated under the SITE 
Program atthe location of a former public watersupply well 
#1 (PWS) in Bendena, Kansas. The primary contaminant 
in the well water was nitrate. Based on historical data, 
nitrate concentrations in the water ranged from 
approximately 20 to 130 ppm, well above the regulatory 
limit of 10 mg/I. Low concentrations of VOCs, particularly 
carbon tetrachloride (CCI 4 ), were a secondary problem. 
The overall goal of EcoMat was to demonstrate the ability 
of its process to reduce the levels of nitrate in the extracted 
groundwater and restore the public water supply well as a 
drinking water source. 


The central goal of EcoMat was to demonstrate that its 
system could produce groundwaterfrom PWS Well # 1 that 
would be in compliance with the drinking water MCLs for 
nitrate-N, nitrite-N, and total-N, while at the same time 
meeting requirements for other parameters such as 
turbidity, pH, residual methanol, suspended solids, and 
biological material. With respect to both the BDN and post¬ 
treatment components of the system, EcoMat proposed the 
following three performance estimates: 

• With incoming groundwater having nitrate-N of 20 
mg/I or greater, and operating at a flow through 
rate of 3-15 gpm, the BDN unit would reduce the 
combined nitrate-N and nitrite-N level (total-N) in 
PWS Well #1 groundwater to at or below a 
combined concentration of 10 mg/I. 

• The posttreatmentorpolishing unit would produce 
treated groundwater meeting applicable drinking 
water standards with respect to nitrate-N (10 mg/I), 
nitrite-N (1 mg/I), and total-N (10 mg/I). 

• Coupled with the planned or alternative post¬ 
treatment, the product water would consistently 
meet drinking water requirements, except for 
residual chlorine. Specifically it would not contain 
turbidity of greater than 1 NTU, detectable levels 
of methanol (1 mg/I), or increased levels of 
biological material or suspended solids, and would 
have a pH in the acceptable 6.5-8.5 range. 

For the purposes of these evaluations, demonstration 
criteria were chosen that, when rounded to the nearest 
whole number, they would be consistent with the Kansas 
Department of Health and Environment (KDHE) MCL 
values. The KDHE MCL values for nitrate-N, nitrite-N, and 
total-N were 10, 1, and 10 mg/I, respectively. Thus, values 
less than the nitrite-N demonstration criterion of 1.5 mg/I 
(i.e., < 1.49 mg/I) would reduce to 1 mg/I. Values less than 
the nitrate-N and total-N demonstration criterion of 10.5 
mg/I (i.e., < 10.49 mg/I) would reduce to 10 mg/I. 


ES-1 



Conclusions from this SITE Demonstration 


• Events 1 and 2 were determined successful in 
meeting the 1 st and 2 nd performance goals. 
Concentrations of total-N, nitrate-N, and nitrite-N 
were significantly reduced to below MCLs 
immediately following BDN treatment and after 
post treatment. 

• Event 3 and 4 were determined not successful in 
meeting the 1 s! and 2 nd performance goals for 
significantly reducing levels of total-N, nitrate-N, 
and nitrite-N after BDN and after post treatment. 

A number of additional conclusions may be drawn from the 
evaluation of the EcoMat BDN and post-treatment 
processes as a whole, based on extensive analytical data 
supplemented by field measurements. These include: 

• The filtration systems incorporated following the 
first event appear to have had a substantial 
beneficial impact on solids carryover. Based on 
laboratory and field measurements, the 5pm high 
efficiency and 1 pm polishing filters used during the 
last two events produced better results for 
reduction of biological material, total suspended 
solids, and turbidity in the final effluent. 

• Specific to turbidity, which has a secondary 
drinking water criterion of 1 Normal Turbidity Unit 
(NTU), average field measurement results for 
Events 3 and 4 final effluents were 1.2 and 0.96 
NTU, respectively. These results were improved 
in comparison to the 1.8 NTU average value for 
Event 2 final effluent, in which “sand filtration" and 
“rough filtration" (20pm) were used; and where 
greatly improved in comparison to the 4.4 NTU 
average value for Event 1 final effluent, in which 
no filtration was used. 

• Total suspended solids (TSS) laboratory results 
were similar to the turbidity field measurements. 
The demonstration criterion forTSS in finaleffluent 
was to be less than or equal to that of the inlet 
water, in which TSS was consistently measured to 
be below the detection limit of 5 mg/I for all four 


events. TSS results for Event 1 were consistently 
above this 5 mg/I threshold and averaged 10 mg/I. 
During Events 2, 3, and 4 TSS was measured 
above 5 mg/I in 3 of 9, 7of 9, and 7 of 8 of the final 
effluentsamples collected, respectively. However, 
the average TSS value for these events was below 
the detection limit of 5 mg/I. 

The demonstration criterion for residual bacterial 
content in the final effluent was also to be less 
than or equal to that of the inlet water. The highest 
bacterial counts in final effluentoccurred for Event 
2. This was likely due to the fact that no 
disinfection (i.e., chlorine, ozone, etc.) was used 
and that“rough”filtration (20 pm)was the smallest 
filtration size used during Event 2. Residual 
bacterial content in the final effluent, decreased 
significantly in Events 3 and 4, likely the result of 
adding “high efficiency" (5pm) and “polishing" 
(1pm) filters to the post-treatment system. 
Nevertheless, the levels of total heterotrophic and 
facultative anaerobe bacterial matter measured in 
the final effluent for all events was well above 
corresponding inlet water levels. 

None of the post treatment system combinations 
used during the demonstration was effective in 
removing residual methanol to the demonstration 
objective of < 1 mg/I. Methanol concentration 
averages in final effluent were between 15 and 98 
mg/I during the four events. Methanol was actually 
measured on average to be higher in the final 
effluent samples than in post BDN samples 
(collected upstream of the post-treatment system) 
for three of the four events. This may be an 
anomaly attributable to ongoing methanol 
degradation in the post BDN samples prior to 
analysis. The final effluent samples were 
disinfected (preserved) so that further reaction was 
halted. 

There appears to be an inverse correlation 
between flow rate and nitrate removal (i.e., higher 
flow rate correlating to less effective nitrate 
removal), based on a per sample round 
comparison of system flow rate and Total-N 
concentration in final effluent. However, it was not 
possible to confirm that this was a cause/effect 
relationship because of (a) the narrow range of 
flows actually investigated and (b) variations in 
performance that occurred or became necessary 
due to upsets, and other operational problems. 


Since the post-treatment system implemented by EcoMat 
varied for each of the four events, data from the four events 
were first analyzed separately. Formal statistical analyses 
were used to address the first two performance estimates 
previously discussed (i.e., total-N level less than 10 mg/I, 
and nitrate-N and nitrite-N levels less than 10 mg/I and 1 
mg/I, respectively), using a significance level of 0.10. The 
overall conclusion from these tests was that: 


ES-2 



pH was not altered by the EcoMat BDN or post¬ 
treatment systems. For Events 1 and 2 there was 
a very slight increase in pH from the inlet water to 
the post BDN effluent. No discernable change in 
pH between inlet water and final effluent was 
measured for Event 3. For Event 4, the pH values 
for inlet water ranged from 8.3 - 9.2 (outside of the 
acceptable drinking water limits of 6.5-8.5). Final 
effluent pH values were slightly lower and ranged 
from 6.8 - 8.9. 

Daily dissolved oxygen (DO) field measurements 
indicated thatthe de-oxygenating stepof EcoMat’s 
BDN process may not have been optimized. The 
desired DO level of partially biodenitrified (partial 
BDN) water in the de-oxygenating tank is < 1 mg/I. 
However, DO values below 1 mg/I were measured 
only during the first two events. Average DO 
during Events 1 and 2 were 1.1 and 1.0 mg/I, 
respectively. DO in partial BDN effluent during 
Event 3 were consistently measured above 1 mg/I 
and averaged 2.1 mg/I. DO in partial BDN effluent 
during Event 4 was also consistently measured 
above 1 mg/I and averaged 2.8 mg/I. Because 
Events 3 and 4 had poorer nitrate removal than 
Event 1 and 2, the inability to optimize the de- 
oxygenating step of the BDN process during the 
last two events could have negatively impacted 


results. 

The quality assurance analyses of critical sample 
data indicated adequate data quality was achieved 
for evaluating the EcoMat technology. With 
respect to data accuracy, the overall 
demonstration recovery average for 44 nitrate-N 
MS/MSD sample sets was approximately 95%. 
The overall demonstration recovery average for44 
nitrite-N MS/MSD sample sets was approximately 
96%. With respect to data precision, the overall 
demonstration average relevantpercentdifference 
for those MS/MSD sets for nitrate-N and nitrite-N 
were 2.7 and 2.1, respectively. 

Carbon tetrachloride, which had been historically 
detected in PWS Well #1 water, was not detected 
in inlet water or final effluent samples. Thus, the 
effectiveness of any of the post-treatment 
combinations fortreating this compound could not 
be evaluated. 

For a 100 gpm system, the estimated cost to treat 
nitrate-contaminated groundwater over a one year 
period is $490,000, or approximately $0.012/gal. 
The cost over 5, 10,or 15 years is estimated to 
increase to approximately$730,000($0.0034/gal.); 
$1,000,000 ($0.0024/gal.) and $1,300,000 

($0.002/gal.), respectively. 


ES-3 

































































. 


















■ 

























































Section 1.0 
Introduction 


This section provides background information about the 
Superfund Innovative Technology Evaluation (SITE) 
Program, discusses the purpose of this Innovative 
Technology Evaluation Report (ITER), and describes 
EcoMat Inc.’s Biological Denitrification (BDN) process. Key 
contacts are listed at the end of this section for inquiries 
regarding additional information about the SITE Program, 
this technology, and the demonstration site. 

1.1 Background 

The EcoMat Inc. BDN process was demonstrated under 
the Superfund Innovative Technology Evaluation (SITE) 
Program at a former public water supply (PWS) well in 
Bendena, Kansas. The demonstration project, which 
occurred in cooperation with the Kansas Department of 
Health and Environment (KDHE), evaluated an ex situ 
anoxic BDN technology developed by EcoMat Inc. of 
Hayward, California. The technology is a type of fixed-film 
biofilter that uses specific biocarriers and naturally 
occurring anoxic bacteria to treat nitrate contaminated 
water. During this demonstration the technology was part 
of an overall system that included four different 
combinations of post-treatment systems. Each of the four 
post-treatment systems included an oxidation component 
to convert residual nitrite back to nitrate. A filtration 
component was included in three of the fourpost-treatment 
systems to remove suspended solids. Both the biological 
denitrification process and post-treatmenttechnology were 
evaluated during this demonstration. 

The well of concern, the Bendena Rural Water District #2 
Public Water Supply (PWS) Well #1, and surrounding 
monitoring wells have been the subject of numerous 
groundwater investigations since 1985. Historical data 
from these investigations revealed elevated concentrations 
of nitrate and carbon tetrachloride (CCI 4 ). The data show 
that nitrate concentrations in the groundwater range from 
approximately 20 to 130 ppm, which is well above the 
National Primary Drinking Water Stan da rds (N PD WS) limit 
of 10 mg/I. The historical data show a history of CCI 4 


concentrations between 2 pg/l and 31 pg/l (the current 
MCL for CCI 4 is 5 pg/l). 

Numerous sampling investigations at PWS Well #1 have 
been unsuccessful in identifying the specific source of 
contamination for both nitrate and CCI 4 . Since the land 
surrounding the city is primarily agricultural, non-point 
runoff of contaminated surface water from agricultural land 
was considered as a possible contamination source for 
nitrate. This explanation was not supported by the low 
concentrations of ammonia (< 0.8 mg/I) found in 
groundwater samples. There was also reason to suspect 
an industrial leak upgradient of the well as the source of 
nitrate, but this has not been confirmed. 

The demonstration project, which occurred between May 
and December 1999, consisted of four separate sampling 
events. During these events, EcoMat operated its system 
with a flow rate between approximately three and eight 
gallons per minute. During this time period, nitrate levels 
in the well water varied from greater than 70 mg/I to 
approximately 30 mg/I. 

The overall goal of EcoMat was to demonstrate the ability 
of its process to reduce the levels of nitrate in the extracted 
groundwater and restore the public water supply well as a 
drinking water source. Specifically, the Primary Objectives 
for this SITE demonstration included the following: 

• demonstrate, that with an incoming groundwater 
nitrate-N concentration of 20 mg/I or greater, and 
operating at a flow rate of 3 to 15 gpm, the BDN 
unit will reduce the combined nitrate-N and nitrite- 
N (i.e., total-N) level in the PWS Well 
#1groundwater to less than 10.5 (which would 
reduce to less than orequal to the MCL of 10 mg/I 
when rounded to a whole number). 

• demonstrate that the post-treatment unit will 
produce treated groundwater that will meet 
applicable drinking waterstandards with respectto 
nitrate-N (i.e., to less than 10.5 mg/I), nitrite-N (i.e., 
to less than 1.5 mg/I) and combined nitrate-N and 


1 



nitrite-N (i.e., to less than 10.5 mg/I). These 
demonstration criteria would reduce to less than or 
equal to the MCLs of 10, 1, and 10 mg/I when 
rounded to whole numbers). 

1.2 Brief Description of the SITE Program 

The SITE Program is a formal program established by the 
EPA's Office of Solid Waste and Emergency Response 
(OSWER)and Office of Research and Development(ORD) 
in response to the Superfund Amendments and 
Reauthorization Act of 1986 (SARA). The SITE Program 
promotes the development, demonstration, and use of new 
or innovative technologies to clean up Superfund sites 
across the country. 

The SITE Program's primary purpose is to maximize the 
use of alternatives in cleaning hazardous waste sites by 
encouraging the development and demonstration of new, 
innovative treatment and monitoring technologies. It 
consists of three major elements: 

• the Demonstration Program, 

• the Consortium for Site Characterization 

Technologies (CSCT), and 

• the Technology Transfer Program. 

The objective of the Demonstration Program is to develop 
reliable performance and cost data on innovative 
technologies so that potential users can assess the 
technology's site-specific applicability. Technologies 
evaluated are either available commercially or close to 
being available for full-scale remediation of Superfund 
sites. SITE demonstrations usually are conducted at 
hazardous waste sites under conditions that closely 
simulate full-scale remediation conditions, thus assuring 
the usefulness and reliability of the information collected. 
Data collected are used to assess: (1) the performance of 
the technology; (2) the potential need for pre- and post¬ 
treatment of wastes; (3) potential operating problems; and 
(4) the approximate costs. The demonstration also 
provides opportunities to evaluate the long term risks and 
limitations of a technology. 

Existing and new technologies and test procedures that 
improve field monitoring and site characterizations are 
explored in the CSCT Program. New monitoring 
technologies, or analytical methods that provide faster, 
more cost-effective contamination and site assessment 
data are supported by this program. The CSCT Program 
also formulates the protocols and standard operating 
procedures for demonstration methods and equipment. 

The Technology Transfer Program disseminates technical 
information on innovative technologies in the 
Demonstration and CSCT Programs through various 
activities. These activities increase awareness and 
promote the use of innovative technologies for assessment 


and remediation at Superfund sites. The goal of 
technology transfer activities is to develop interactive 
communication among individuals requiring up-to-date 
technical information. 

1.3 The SITE Demonstration Program and 
Reports 

In the past technologies have been selected for the SITE 
Demonstration Program through annual requests for 
proposal (RFP). EPA reviewed proposals to determine the 
technologies with promise for use at hazardous waste 
sites. Several technologies also entered the program from 
currentSuperfund projects, in which innovative techniques 
of broad interest were identified for evaluation under the 
program. 

Once the EPA has accepted a proposal, cooperative 
arrangements are established among EPA, the developer, 
and the stakeholders. Developers are responsible for 
operating their innovative systems at a selected site, and 
are expected to pay the costs to transport equipment to the 
site, operate the equipment on-site during the 
demonstration, and remove the equipment from the site. 
EPA is responsible for project planning, sampling and 
analysis, quality assurance and quality control, preparing 
reports, and disseminating information. Usually, results of 
Demonstration Programs are published in three 
documents: the SITE Demonstration Bulletin, the 
Technology Capsule, and the Innovative Technology 
Evaluation Report (ITER). The Bulletin describes the 
technology and provides preliminary results of the field 
demonstration. The Technology Capsule provides more 
detailed information aboutthe technology, and emphasizes 
key results ofthe SITE field demonstration. 

The ITER provides detailed information on the technology 
investigated, a categorical cost estimate, and all pertinent 
results of the SITE field demonstration. An additional 
report, the Technology Evaluation Report (TER), is 
available by request only. The TER contains a 
comprehensive presentation of the data collected during 
the demonstration and provides a detailed quality 
assurance review ofthe data. 

For the EcoMat Inc. Biological Denitrification process 
demonstration, there is a SITE Technology Bulletin, 
Capsule, and ITER; all of which are intended for use by 
remedial managers for making a detailed evaluation of the 
technology for a specific site and waste. A TER is also 
submitted for this demonstration to serve as verification 
documentation. 

1.4 Purpose of the Innovative Technology 
Evaluation Report (ITER) 

This ITER provides information on both 1) EcoMat Inc.’s 
Biological Denitrification process for treatment of nitrate in 


2 



water and on 2 ) the post-treatment system fortreatment of 
organics (e.g., VOCs, methanol), solids and microbes in 
water. This report includes a comprehensive description of 
this demonstration and its results. The ITER is intended for 
use by EPA remedial project managers, EPA on-scene 
coordinators (OSCs), contractors, and other decision¬ 
makers carrying out specific remedial actions. The ITER 
is designed to aid decision-makers in evaluating specific 
technologiesforfurtherconsideration as applicable options 
in a particular cleanup operation. This report represents a 
critical step in the development and commercialization of a 
treatment technology. 

To encourage the general use of demonstrated 
technologies, the EPA provides information regarding the 
applicability of each technology to specific sites and 
wastes. The ITER includes information on cost and 
desirable site-specific characteristics. It also discusses 
advantages, disadvantages, and limitations of the 
technology. 

Each SITE demonstration evaluates the performance of a 
technology in treating a specific waste matrix. The 
characteristics of other wastes and other sites may differ 
from the characteristics of the treated waste. Therefore, a 
successful field demonstration of a technology at one site 
does not necessarily ensure that it will be applicable at 
other sites. Data from the field demonstration may require 
extrapolation for estimating the operating ranges in which 
the technology will perform satisfactorily. Only limited 
conclusions can be drawn from a single field 
demonstration. 

1.5 Technology Description 

Fixed film bioremediation using a biocarrier is the treatment 
of contaminated groundwater using bacteria appropriate to 
the contaminants of concern attached to some form of 
supporting substrate. Using EcoMat’s patented mixed 
reactor, the biocarrier is designed to be retained in the 
system, thereby minimizing solids carryover. In the case 
of the Bendena water well, elevated nitrate in the 
groundwater is the primary problem; low concentrations of 
volatile organic compounds (VOCs) (particularly CCI 4 ) are 
a secondary problem. Fixed film treatment allows rapid 
and compact treatment of nitrate with minimal byproducts. 
Methanol is added as a source of carbon for the metabolic 
processes and cell growth of the bacteria that convert the 
nitrate to nitrogen gas. 

The mechanism for anoxic biodegradation of nitrate 
consists of initial removal of excess oxygen followed by 
two sequential reactions as shown in the following 
equations. 

Oxygen Removal: 

CH 3 OH + 1.50 2 .> C0 2 + 2H 2 0 (1) 


Denitrification Step 1: 

CH 3 OH + 3N0 3 .> 3N0 2 '+ C0 2 + 2H 2 0 (2) 

Denitrification Step 2: 

CH 3 OH + 2N0 2 .> N 2 + C0 2 + 20H + H 2 0 (3) 

Overall Denitrification Reaction: 

5CH 3 OH + 6N0 3 .> 3N 2 + 5C0 2 + 60H + 7H 2 0 (4) 

Note: The subsequent discussion refers to nitrate- and 
nitrite-nitrogen values (nitrate-N and nitrite-N, respectively), 
in which each mg/I of nitrate-N is equivalent to 4.4 mg/I of 
nitrate and each mg/I of nitrite-N is equivalent to 3.2 mg/I of 
nitrite. 

Available oxygen must first be consumed to a dissolved 
oxygen concentration of < 1 mg/I so that the bacteria are 
forced to substitute the nitrate as the electron acceptor 
(Equation 1). The nitrate is then reduced to nitrite (Equation 
2). In Equation 3, the nitrite is further reduced to nitrogen 
gas. The overall denitrification reaction is presented in 
Equation 4. 

Nitrite production is an intermediate step and there is no a 
priori reason to assume that the second reaction is at least 
as fast and/or favored as the first reaction in the presence 
of a specific bacterial population. Consequently, any 
evaluation scheme must establish that there is no buildup 
of nitrite, particularly since the nitrite-nitrogen MCL is 1 
mg/I, one-tenth that of nitrate. High concentrations of 
nitrate and high nitrate/methanol ratios may also affect the 
concentration of residual nitrite. 

The effluent from the denitrification system will contain 
small amounts of bacteria and suspended solids which 
must be removed by a post-treatment system, and also 
may contain some concentration of nitrite. EcoMat can 
incorporate an oxidation component (ozonation and/or 
ultraviolet (UV) disinfection) into its post-treatment system 
to accomplish some degree of chlorinated hydrocarbon 
destruction as well as oxidation of remaining nitrite back to 
nitrate, oxidation of any residual methanol, and destruction 
of bacterial matter. A filtration component can also be 
incorporated into the post-treatment system to remove 
suspended solids. Although ozonation and UV oxidation 
may also result in disinfection of treated water, additional 
chlorination would also be required before the treated water 
could be used as a drinking water supply in Kansas. 

Although this demonstration is being carried out on drinking 
water, anoxic BDN using a biocarrier should be applicable 
to industrial waste waters as well as leachate from 
commercial, industrial, and hazardous waste sites 
containing various levels of nitrate. The presence of other 
contaminants could play a significant role in the 
effectiveness and viability of the overall treatment system. 
The post treatment system components selected for the 
Bendena site were intended to produce final effluent that 
met drinking water standards for nitrate and nitrite and to 


3 







also provide some removal of methanol. If the planned 
ozonation system proved to be inadequate for VOC 
removal, EcoMat had planned to reactivate an inactive air 
stripper at the site. With more complex waste waters, the 
post-treatment system may play a larger role in the overall 
effectiveness of the total system. 

Design of the treatment process/system fora particular site 
requires the characterization of the contaminant types, 
concentrations, and variability in the water source that will 
become the feed to the system. This information is used to 
properly size the BDN unit and the post-treatment system. 
For the Bendena site, it was also necessary to assure that 
discharge of the treated water to a septic system did not 
unintentionally recharge the aquifer in such a way as to 
significantly alter (decrease) the nitrate (or chlorinated 
hydrocarbon) content of the aquifer feeding PWS Well #1. 

1.6 Key Contacts 

Additional information regarding EcoMat Inc.’s Biological 
Denitrification process, the company’s other treatment 
processes, and the SITE Program can be obtained from 
the following sources: 

Technology Developer 

EcoMat Inc. 

Peter Hall 

26206 Industrial Blvd. 

Hayward, CA 94545 
Phone: (510) 783-5885 
Fax: (510) 783-7932 

e-mail: info@ecomatinc.com 
www.ecomatinc.com 


The SITE Program 

Mr. Robert A. Olexsey 

Director, Land Remediation and Pollution Control Division 

National Risk Management Research Laboratory 

U.S. Environmental Protection Agency 

26 West Martin Luther King Drive 

Cincinnati, OH 45268 

(513) 569-7861 

FAX: 513-569-7620 

Mr. Randy Parker 

U.S. EPA SITE Project Manager 

National Risk Management Research Laboratory 

U.S. Environmental Protection Agency 

26 West Martin Luther King Drive 

Cincinnati, OH 45268 

(513) 569-7271 

e-mail: Parker.Randv@epa.gov 

Information on the SITE Program is available through the 
following on-line information clearinghouses: 

• The SITE Home page (www.epa.gov/ORD/SITE) 
provides general program information, current 
project status, technology documents, and access 
to other remediation home pages. 

• The OSWER CLU-ln electronic bulletin board 
(http://www.clu-in.org) contains information on the 
status of SITE technology demonstrations. The 
system operator can be reached at (301) 585- 
8368. 

Technical reports may be obtained by writing to 
USEPA/NSCEP, P.O. Box 42419, Cincinnati, OH 45242- 
2419, or by calling 800-490-9198. 


4 





Section 2.0 

Technology Applications Analysis 


This section addresses the general applicability of the 
EcoMat Inc. BDN Technology to sites containing 
groundwater contaminated with nitrate. The analysis is 
based on results from and observations made during the 
SITE Program demonstration and from additional 
information received from EcoMat Inc. SITE demonstration 
results are presented in Section 4 of this report. The 
vendor had the opportunity to discuss the applicability, 
other studies and performance of the technology in 
Appendix A. 

2.1 Key Features of the BDN and Post- 
Treatment Processes 

The EcoMat Inc. BDN Technology is designed to quickly 
and effectively treat nitrate-contaminated groundwater 
while generating minimal byproducts. This system is 
appropriate for treating potential drinking water supplies 
and may also be effective in treating industrial wastewater 
or leachate from commercial, industrial, and hazardous 
waste sites. The system may be most suitable for treating 
water supplies in agricultural regions that are subject to 
increased nitrate concentrations due to seasonal fertilizer 
application. The system can also treat inorganic pollutants, 
other than nitrate, through cultivation of different types of 
microbes. 

The EcoMat Inc. BDN Technology is a fixed-film 
bioremendiation process using a biocarrier and bacteria 
appropriate to the contam inant of concern. In the case of 
the Bendena water well, the contaminant of concern is 
nitrate. EcoMat’s patented mixed reactor retains the 
biocarrier in the system, thereby minimizing solids 
carryover. In addition, the fixed film treatment allows rapid 
and compact treatment of nitrate with minimal byproducts. 
Overall, the denitrification process is intended to convert 
nitrates in the groundwater to nitrogen gas. In addition to 
demonstrating EcoMat’s BDN Technology, the project also 
included demonstration of a post-treatment system 
designed to destroy or remove any intermediate 


compounds potentially generated during the biological 
breakdown of the nitrate (e.g., nitrite), and also remove 
small amounts of bacteria and suspended solids that are 
not attached to the biocarrier. Treatment of VOCs present 
in the influent can also be accomplished by the post¬ 
treatment system by incorporating traditional treatment 
methods, such as ozonation and air stripping. 

The denitrification process is accomplished in two reactors. 
Reactor 1 (R1), referred to as the “De-oxygenating Tank," 
includes bioballs loaded with denitrifying bacteria. These 
bacteria are fed a 50 percent aqueous methanol solution to 
act as a carbon source for the metabolic processes that 
remove free oxygen and to act as a carbon source for cell 
growth. The second reactor (R2), which receives the de- 
oxygenated water from Reactor 1, is packed with 1-cubic 
centimeter (cm 3 ) cubes of a synthetic sponge-like 
polyurethane biocarrier called “EcoLink.” The Ecolink 
medium hosts the colonies of bacteria cultured for 
degrading nitrate. An important feature to this medium is 
that small contiguous holes are incorporated into the 
medium to maximize surface area for the active bacteria 
colony and to permit the exit of the nitrogen gas formed 
during the denitrification process. 

Reactor 2 also includes a specially designed mixing 
apparatus to direct the incoming de-oxygenated water into 
a circular motion, thus keeping the media in constant 
circulation and maximizing contact between the water and 
media. Methanol is also fed to this reactor to encourage 
nitrate consumption and to act as a carbon source for the 
anaerobic bacteria degrading the nitrate to nitrogen gas. 
The effluentfrom R2 received additional treatment, referred 
to here as post-treatment. During the course of the 
demonstration, four different combinations of post¬ 
treatment were incorporated into the overall treatment 
system. Each of the four systems utilized during the 
demonstration incorporated one or more oxidation 
components, such as chlorination, ultraviolet (UV) light, or 
ozonation. In addition to destroying any active bacteria 
exiting the BDN system, the oxidation component was 


5 



designed to oxidize: 1) residual nitrite back to nitrate 2) 
residual methanol, and 3) VOCs in the water (e.g., CCI 4 ). 

During the majority of the demonstration, the post¬ 
treatment system also incorporated a filtration component 
designed to remove suspended solids generated from the 
BDN process. In addition to using a clarifying tank, a 
variety of filter combinations were used, including a sand 
filter, a carbon filter, and different sized cartridge filters (i.e., 
rough, high efficiency, and polishing filters). 

The developer believes that the denitrification technology 
is capable of effectively converting nitrate and methanol to 
nitrogen gas and carbon dioxide. This aspect was of 
primary interestforthis demonstration. The developer also 
claims that the post-treatment or polishing step can 1) 
oxidize any residual nitrite to nitrate, 2) oxidize residual 
methanol, 3) destroy bacterial matter exiting the EcoMat 
reactor, and 4) remove suspended solids. No claim was 
made concerning the removal of VOC’s. 

2.2 Operability of the Technology 

The prime factor in determining the effectiveness of the 
EcoMat Inc. BDN Technology is the growth of a healthy 
population of naturally-occurring anoxic bacteria 
(denitrifiers) to reduce nitrate to nitrogen gas and carbon 
dioxide in the presence of methanol. The growth of these 
denitrifiers is dependant upon a number of factors including 
nitrate-N concentration, pH, temperature, and carbon 
concentration. In addition, continuous operation with 
minimal process disruptions, including shutdowns, is critical 
to maintaining a healthy microbial population. Overall, the 
EcoMat technology is designed to provide optimum 
conditions for growing and sustaining an active bacteria 
colony. 

The EcoMat technology is an ex situ process consisting of 
a BDN and a post-treatment system. The BDN system 
includes two reactors in series, followed by an overflow 
tank. Each reactor is two cubic meters in size with a water 
capacity of approximately 1,100 gallons. The first reactor 
(R1), referred to as the “Deoxygenating Tank” is equipped 
with ports for both the tank’s influent and effluent, and a 
methanol feed. The second reactor (R2), referred to as the 
“EcoMat Reactor,” is also equipped with ports for the 
influent, effluent, and methanol feed. The final component 
of the BDN system is a small overflow tank capable of 
holding approximately 200 gallons. 

Prior to system start-up, a shakedown period is required to 
begin BDN by developing the necessary biological growth 
on the “biocarrier” in the bioreactor chamber under full 
recycle. The shakedown period normally takes 
approximately six weeks. This 6-week period gives the 
system operators an opportunity to adjust water flow and 
methanol feed rates based on observed nitrate and nitrite 
concentrations and other factors. 


Since each of the reactors maintains large populations of 
sensitive microbes, continuous operation of the system is 
critical. The growth of denitrifying bacteria on the biocarrier 
in the Deoxygenating Tank is dependent upon achieving 
both a relatively low dissolved oxygen concentration (e.g., 
-1 mg/I) and an environment rich in carbon. As a result, 
methanol is routinely fed to the De-oxygenating Tankto act 
as the source of carbon. To ensure that a healthy 
population of denitrifiers is maintained, routine monitoring 
of the methanol concentration is performed. 

The Deoxygenating Tank requires little attention and 
maintenance. The groundwater simply enters the top of 
the reactor, flows through the bioballs and exits the bottom 
of the reactor. Level switches near the top of the tank 
control flow into the tank; these do require routine service. 

Continuous operation of the EcoMat Reactor is also critical. 
Specialized bacteria for degrading nitrate are cultured in 
this reactor. Since an anaerobic environment is necessary 
to accomplish denitrification, dissolved oxygen levels are 
routinely monitored to ensure a concentration of less than 
1.0 mg/I. 

The EcoMat Reactoris equipped with a patented mixerthat 
is designed to circulate the water within the reactor without 
the aid of moving parts. This reactor contains EcoLink 
media which also are circulated by the mixing apparatus. 
Like the de-oxygenating tank, the EcoMat Reactor also 
requires minimal operational attention and maintenance. 
The most common maintenance activity would be periodic 
replacement of the EcoLink biocarrier, which occasionally 
becomes overloaded and falls out of suspension. 

Specific to the demonstration, delivery of the groundwater 
to the treatment system was accomplished by a 
submersible pump installed within PWS Well #1. The 
submersible pump was originally controlled by a float 
switch in Reactor #1. To prevent potential burn-out of the 
submersible pump, the float switch was replaced first with 
a pressure switch and finally with a “flapper.” The line 
delivering the groundwater to the treatment system was 
equipped with a totalizer to monitor flow rate. Totalizers 
were also installed at the treatment system discharge point 
and on the recycle line for the SITE evaluation. 

The post-treatment system included different treatment 
com ponents during each of the four demonstration events. 
The four post-treatment scenarios are presented below. 


Event 1 - 

Chlorination 

Event 2 - 

Clarification, Sand & 
Rough (20pm) Filtration, 
and UV Oxidation 

Event 3 - 

Ozone, UV Oxidation, 
Clarification, Rough 
(20pm) & High Efficiency 


6 



(5|jm) Filtration, Carbon 
Adsorption, & Polishing 
(1pm) Filtration 

Event 4 - Chlorination, 

Clarification, High 
Efficiency (5pm filter) 

Filtration, Air Stripping, 
and Polishing (20pm) 

Filtration 

Each component used in the post-treatment system was 
purchased "off the shelf” from equipment suppliers. 
Operation of the equipment was learned in the field during 
the demonstration period and appropriate adjustments to 
feed and flow rates were made to maximize the 
effectiveness of treatment. General maintenance of the 
post-treatment system during the demonstration included 
flushing out the entire post-treatment system, back 
washing of the sand filter, drainage of the clarifier, and 
replacement of the cartridge filters. 

Both the BDN and post-treatment systems were installed 
inside a storage building that was twelve feet wide, twenty 
feet long, and twelve feet high. The shed was equipped 
with 1) electricity to operate pumps and provide heat, 2) a 
potable water supply for cleanup and decontamination 
activities, and 3) a telephone and facsimile machine 
hookup. The shed also provided sufficient work space and 
room for storage of equipment and reagents. 

The process, including both the BDN and the post¬ 
treatment system, was designed to operate unattended; 
however, during the four sampling events seven system 
shutdown periods required the presence of on-site 
personnel to address the operational problems and bring 
the system back online. Shutdowns were caused by a 
combination of mechanical problems and electrical storms 
causing power outages. Numerous shutdowns during 
sampling Event 2 resulted in a decision to abort the event 
and restart when mechanical problems were corrected. It 
should be noted that additional shakedown periods were 
required after some of the shutdowns to reestablish 
microbial populations in the reactors. 

2.3 Applicable Wastes 

The EcoMat BDN technology is an ex situ fixed- film BDN 
system designed to destroy or remove nitrates in water. In 
addition to using the technology on a potential drinking 
water source during this demonstration, the technology 
should be applicable to industrial wastewaters and 
leachate from commercial, industrial, and hazardous waste 
sites containing elevated nitrate concentrations. 

During the demonstration, a post-treatment system 
designed to remove chlorinated hydrocarbons from water 
was also evaluated. The developer also claims that the 


technology is suitable for treating other types of inorganic 
pollutants since the EcoMatreactorcan effectively cultivate 
microbes that can degrade different contaminants. 

An EcoMat biological reactor is currently being used at a 
Department of Defense facility in Southern California to 
treat perchlorate. Also, there are EcoMat systems installed 
at aquariums for removing nitrate from saltwater. 

2.4 Availability and Transportability of 
Equipment 

The EcoMat Biological Denitrification and Post-Treatment 
Process requires a level pad, ideally concrete, and a 
heated building. The size of the pad and building is 
dependent on the size of the process installed at a 
particular site. EcoMat has indicated that it is feasible to 
install a treatment system outside, which may be 
necessary for very large systems. In such instances, heat 
tracing would be installed to provide temperature control. 

At the Bendena site, the process consisted of a 
Deoxygenating Tank, the EcoMat Reactor, an overflow 
tank, and the post-treatment system (ozone unit, UV 
treatment, clarifier, sand filter, cartridge filters, air stripper, 
and carbon filters). This entire process (except for the 
existing air stripper) and necessary support equipment fit 
inside a shed that was twelve feet wide, twenty feet long, 
and twelve feet high. Since this system is designed to be 
unattended, a trailer or additional office space in the 
building housing the process should not be necessary. 

Equipment and supplies associated with the process were 
transported to the site by one truck. Each two cubic meter 
(m 3 ) reactor tank was delivered to the site in halves to 
permit for easy handling and assembly. The remainder of 
the treatment units and associated equipment can be 
handled and installed by one person. 

Depending on well availability at sites intending to use this 
technology, a drill rig with associated drilling equipment 
might be necessary. Fortunately, during this demonstration 
a former railroad well constructed in the early 1900's 
served as the source for the nitrate-contaminated 
groundwater. The total well depth is 73.4 feet below 
ground surface (bgs) and the static water level is 
approximately 45 bgs; the inside well diameter is 
approximately 23 feet. 

During the demonstration the EcoMat BDN and Post- 
Treatment systems required periodic maintenance of a 
number of process units and replacement was necessary 
for a number of units. Some of the equipment changes 
necessary during system operation included new pressure 
switches for controlling tank levels, new PVC piping and 
hoses to rectify leaks, and new filters to prevent filter 
microbial buildup. All replacement equipment was either 
purchased locally or delivered to the site via courier. 


7 



Treated water from the system was discharged to a 1,000 
gallon septic system specifically purchased and installed 
for the demonstration. Heavy equipment such as a 
backhoe may be required for septic system installation. 

If the application for septic system installation had been 
denied due to reasons such as a percolation, slope, depth 
to groundwater, etc., other discharge options would have 
been investigated. During this demonstration numerous 
options were available including discharge to 1) a down 
slope drainage network, 2) a return line back to the PWS 
Well #1, or 3) the ground up gradient of PWS Well #1. 
Ultimately, the intent of this system is to treat the water to 
meet drinking water standards. Therefore, in an actual 
installation treated water would be routed directly into the 
distribution system for delivery to customers in the 
community. Therefore, the availability and transportability 
of equipment related to delivery of water into a specific 
distribution system would need to be investigated. 

2.5 Materials Handling Requirements 

The major materials handling requirement for the EcoMat 
BDN and Post-Treatment systems was installation of the 
individual process units which make-up the treatment 
system. The KDHE provided a shed and a pumped line 
from PWS Well #1 to the shed. The shed included all 
necessary services such as potable water, electricity, heat 
and a phone line. 

The entire system was delivered to the site on one truck. 
Installation of the system required the support of one 
person over a period of approximately one week. All 
process units and associated equipment are small and light 
enough to permit this one person to unload and install the 
equipment. 

Prior to beginning the demonstration, a variety of activities 
were necessary to prepare the BDN and Post-Treatment 
systems for start-up, including a shake down of the 
equipment. The materials handling requirements for 
bringing water from the well were minimal since a pumping 
and groundwater delivery system had already been 
installed within the PWS well. 

The shakedown period simply involved developing the 
necessary biological growth on the “biocarrier” in the 
bioreactor chamber. With the exception of more frequent 
sampling and adjustments to water flow and methanol feed 
rates,the activities performed during the shakedown period 
were no different from those that would be performed 
during routine operation of the system under normal 
conditions. 

If the BDN and Post-Treatment systems are utilized to treat 
groundwater, installation of one or more wells may be 
necessary. Drilling services are generally subcontracted to 
a company which has both the required equipment (drill 
rigs, augers, samplers) and personnel trained in drilling 


operations and well construction. If work is to be 
performed on a hazardous waste site, drilling personnel 
must have the OSHA-required 40-hour health and safety 
training. Once the well(s) are drilled each must be 
equipped with a pump to deliver the groundwater to the 
treatment system. An equalization tank may be necessary 
to store the feed water rather than pumping directly to the 
system. All pumps chosen must be able to perform under 
a variety of conditions. 

Depending on the characteristics of the source water, 
installation of a pretreatment system may be required. 
Parameters in the source water that may cause inhibition 
of the BDN system include pH, dissolved oxygen, 
temperature, and heavy metals. 

The BDN system does not generate any hazardous 
residuals; however, extremely small quantities of non- 
hazardous residuals are generated by various units in the 
post-treatment system. Sludge is generated by the 
clarifying tank and the cartridge filters periodically become 
clogged and need to be flushed or replaced. Residuals 
generated during the demonstration included spent filter 
cartridges and biocarrier media; these were placed in 
plastic trash bags and discarded in an on-site dumpster. 

2.6 Range of Suitable Site Characteristics 

Locations suitable for on-site treatment using the EcoMat 
Denitrification and Post-Treatment System must be able to 
provide relatively uninterrupted electrical power and 
potable water for cleanup activities. Electrical power was 
required fora control panel equipped with high level alarms 
and reset buttons, and for operation of several electrically 
driven pumps throughout the system, including a 
submersible pump to draw water from the well. Power was 
also required to provide heat to the shed via an electrical 
heater. Heat was necessary to maintain a minimum water 
temperature of 60°F in the treatment system and to protect 
equipment and personnel during cold temperatures. 
Overall, the EcoMat Biological Denitrification System 
requires a 115-volt, 3-phase electrical service. During the 
four demonstration sampling events the average and 
maximum energy usage for the overall system were 8.2 
kW-hr and 12.6 kW-hr, respectively. 

There were minimal storage space requirements for 
process chemicals. Process chemicals required for the 
demonstration included 50% methanol aqueous solution 
and a liquid chlorine solution. The methanol solution was 
stored in a 100-gallon plastic tank near the de-oxygenating 
and EcoMat reactors. The chlorine solution was stored in 
a 5-gallon pail beside the post- treatment system. Any 
reagents required for system monitoring (e.g., Nitrate-N, 
Nitrite-N, DO, pH, etc.) were stored in small Styrofoam 
shipping containers on shelving inside the shed. All 
process residuals (spent filters and biocarriers, clarifier 


8 



sludge) were placed in plastic trash bags and stored in the 
shed until final disposal as domestic trash. 

2.7 Limitations of the Technology 

The EcoMat BDN technology is a treatment system 
designed to remove excess nitrate and, with appropriate 
post-treatment may also remove chlorinated hydrocarbons 
(e.g., CCI 4 ), methanol, and microorganisms. The maximum 
removal of nitrates was achieved during the demonstration 
when the flow through the system was in the 3.0 - 5.0 gpm 
range. At this flow rate it is obvious that the system would 
not be appropriate for supplying large residential 
communities with adequate supplies of treated water. The 
system may be more applicable to reducing or eliminating 
nitrate in small community water supplies, in industrial 
wastewaters, or in the leachate from commercial, industrial, 
or hazardous waste sites. 

The growth of healthy microbial populations within each of 
the system’s reactors is the key factor in determining the 
effectiveness of the technology. The growth of these 
organisms is dependant upon factors such as a sufficient 
source of carbon, a continuous low dissolved oxygen 
concentration (< 1.0 mg/I), an acceptable steady pH and 
temperature range, and intimate contact between the 
biocarrier and contaminated water. Also, like most 
biological systems, the system can be inhibited by toxics 
(e.g., heavy metals) in the source water. Many of these 
factors are dependent upon a system that has minimal 
operational/mechanical problems and system shutdowns. 

During the course of the demonstration project, the 
EcoMat Biological Denitrification System, which is designed 
to operate unattended, had numerous 
operational/mechanical problems that required immediate 
attention from on-site demonstration staff. System 
shutdowns occurred on approximately seven occasions; 
two of which occurred due to electrical storms and five 
occurring from system mechanical problems. A number of 
other operational problems occurred, impacting effluent 
quality but not causing system shutdown. 

The majority of operational/mechanical problems 
encountered during the demonstration were remedied 
quickly; normally within minutes to a couple hours of 
learning of the problem. However, during the second 
sampling event, a faulty compressor switch in the de- 
oxygenating tank caused a chain-reaction of other 
problems downstream of the tank, thereby forcing the 
demonstration team to abort the event. 

It should be noted that the SITE team was not present 
during periods between the four events to monitor system 
perturbations (if they occurred). System shutdowns 
occurring during demonstration events that were not 
caused by an electrical storm are summarized below: 

• Just prior to starting Event 2 (in July 1999) 


compressor switches in the de-oxygenating tank 
failed to monitor the water level in the tank. This 
prevented the switch from controlling the 
submersible pump delivering water from the well to 
the system. The malfunctioning switches were 
replaced with a “flapper” to control flow to the tank. 
This delayed the start of Event 2. 

• Replacement of the compressor switch in the de- 
oxygenating tank required system shutdown and 
drainage of the tank. This maintenance activity 
caused the biocarrier to settle in the EcoMat 
reactor and clog the lower perforated screen used 
to separate the biocarrier mixing zone from the 
lower portion of the reactor. EcoMat drained the 
water level in the tank to allow pressure washing 
of the screen. The draining disrupted the microbe 
colonies and further delayed the start of Event 2. 

• Activation of the high level alarm occurred on four 
separate occasions while no high levels were 
observed. The high level alarm shuts off the pump 
routing water to the EcoMat reactor. The 
shutdowns occurred twice during the aborted 
Event 2 in early July 1999, and twice again during 
Event 3 in October 1999. 

• Towards the end of Event 3, a high level alarm 
was activated and the system was shut down due 
to excessive biological growth occurring on one of 
the post-treatment system filters. The filters were 
bypassed to complete the sampling event. 

As stated earlier, other problems encountered during the 
demonstration affected the concentrations of parameters 
that are critical to treatment effectiveness and compliance 
with federal drinking water standards. These problems are 
summarized below. 

• During Event4 EcoMat discovered airentering the 
de-oxygenating reactor via the reactor feed pump. 
This increased the dissolved oxygen concentration 
in the reactor and disrupted the anoxic 
environment inhabited by the denitrifiers. EcoMat 
switched pumps to mitigate the problem. 

• An ozone leak was found in the post-treatment 
system at the start of Event 3. This leak reduced 
the system’s ability to oxidize residual nitrite to 
nitrate, oxidize residual methanol, and destroy 
bacteria. EcoMat replaced a leaking hose soon 
after the leak was discovered via gas detector tube 
monitoring. 

• The pump feeding methanol either malfunctioned 
or was inadvertently turned off during Event 4. 
With no methanol being fed into the system, there 
was no carbon source for bacterial cell growth and 
nitrate consumption was reduced. 


9 



• Significant solids carryover from the BDN system 
to the post-treatment system caused unexpected 
frequent maintenance on the filters and clarifier. 
This occurred routinely during Event 2, when filters 
were first incorporated into the post-treatment 
system. Maintenance activities included replacing 
filters, back washing filters, and draining the 
clarifier. Also, large concentrations of heterotrophic 
bacteria and high turbidity readings in the system’s 
final effluent made the water unacceptable for 
drinking purposes. 

• High methanol concentrations (range: 14.6 - 98 
mg/I) in the final effluent also made this water 
unacceptable for drinking purposes. These high 
methanol concentrations were caused by 
excessive feed rates, or by the failure of the post¬ 
treatment systems to oxidize residual methanol. 

2.8 ARARS for the EcoMat BDN 
Technology 

This subsection discusses specific federal environmental 
regulations pertinent to the operation of the EcoMat 
Biological Denitrification and Post-Treatment processes 
including the transport, treatment, storage, and disposal of 
wastes and treatment residuals. These regulations are 
reviewed with respect to the demonstration results. State 
and local regulatory requirements, which may be more 
stringent, must also be addressed by remedial managers. 
Applicable or relevant and appropriate requirements 
(ARARs) include the following: (1) the Comprehensive 
Environmental Response, Compensation, and Liability Act; 
(2) the Resource Conservation and Recovery Act; (3) the 
Clean Air Act; (4) the Clean Water Act; (5) the Safe 
Drinking Water Act, and (6) the Occupational Safety and 
Health Administration regulations. These six general 
ARARs are discussed below; specific ARARs that may be 
applicable to the EcoMat BDN and Post-Treatment 
Process are identified in Table 2-1. 

2.8.1 Comprehensive Environmental Response, 
Compensation, and Liability Act (CERCLA) 

The CERCLA of 1980 as amended by the Superfund 
Amendments and Reauthorization Act (SARA) of 1986 
provides for federal funding to respond to releases or 
potential releases of any hazardous substance into the 
environment, as well as to releases of pollutants or 
contaminants that may present an imminent or significant 
danger to public health and welfare or to the environment. 
As part of the requirements of CERCLA, the EPA has 
prepared the National Oil and Hazardous Substances 
Pollution Contingency Plan (NCP) for hazardous 
substance response. The NCP is codified in Title 40 Code 
of Federal Regulations (CFR) Part 300, and delineates the 


methods and criteria used to determine the appropriate 
extent of removal and cleanup for hazardous waste 
contamination. 

SARA states a strong statutory preference for remedies 
thatare highly reliable and provide long-term protection. It 
directs EPA to do the following: 

• use remedial alternatives that permanently and 
significantly reduce the volume, toxicity, or the 
mobility of hazardous substances, pollutants, or 
contaminants; 

• select remedial actions that protect human health 
and the environment, are cost-effective, and 
involve permanent solutions and alternative 
treatment or resource recovery technologies to the 
maximum extent possible; and 

• avoid off-site transport and disposal of untreated 
hazardous substances or contaminated materials 
when practicable treatment technologies exist 
[Section 121(b)]. 

In general, two types of responses are possible under 
CERCLA: removal and remedial action. Superfund 
removal actions are conducted in response to an 
immediate threat caused by a release of a hazardous 
substance. Many removals involve small quantities of 
waste of immediate threatrequiring quick action to alleviate 
the hazard. Remedial actions are governed by the SARA 
amendments to CERCLA. As stated above, these 
amendments promote remedies that permanently reduce 
the volume, toxicity, and mobility of hazardous substances 
or pollutants. The EcoMat BDN and post-treatment 
systems are likely to be part of a CERCLA remedial action 
since the toxicity of the contaminants of concern is reduced 
by either denitrification oroxidation. Remedial actions are 
governed by the SARA amendments to CERCLA. On-site 
remedial actions must comply with federal and more 
stringent state ARARs. ARARs are determined on a site- 
by-site basis and may be waived under six conditions: (1) 
the action is an interim measure, and the ARAR will be met 
at completion; (2) compliance with the ARAR would pose 
a greater risk to health and the environment than 
noncompliance; (3) it is technically impracticable to meet 
the ARAR; (4) the standard of performance of an ARAR 
can be met by an equivalent method; (5) a state ARAR has 
not been consistently applied elsewhere; and (6) ARAR 
compliance would not provide a balance between the 
protection achieved at a particular site and demands on the 
Superfund RPM for other sites. These waiver options 
apply only to Superfund actions taken on-site, and 
justification for the waiver must be clearly demonstrated. 


10 



Table 2-1. Federal and State ARARs for the EcoMat BDN Process. 


Process 

Activity 

ARAR 

Description 

Basis 

Response 

Characteriza¬ 
tion of 
untreated 
waste 

RCRA: 40 

CFR Part 261 
(or state 
equivalent) 

Standards that 
apply to 

identification and 
characterization of 
wastes. 

Chemical and physical properties of 
waste determine its suitability for 
treatment by the EcoMat BDN 

Process. 

Chemical and physical analyses 
must be performed to determine 
if waste is a hazardous waste. 


RCRA: 40 

CFR Part 264 
(or state 
equivalent) 

Standards apply to 
treatment of 
wastes in a 
treatment facility. 

Applicable or appropriate for the 
EcoMat BDN Process. 

When hazardous wastes are 
treated, there are requirements 
for operations, record keeping, 
and contingency planning. 

Waste 

Processing 

CAA: 40 CFR 
Part 50 
(or state 
equivalent) 

Regulations govern 
toxic pollutants, 
visible emissions 
and particulate 
matter. 

During process operations, any off¬ 
gases (i.e., from ozonation, air 
stripping, etc.) must not exceed limits 
set for the air district of operation. 
Standards for monitoring and record 
keeping apply. 

Off-gases may contain volatile 
organic compounds or other 
regulated substances; although, 
levels are likely to be very low. 


RCRA: 40 

CFR Part 264 
Sub-part J 
(or state 
equivalent) 

Regulation governs 
standards for tanks 
at treatment 
facilities. 

Storage tanks for liquid wastes (e.g., 
decontamination waste) must be 
placarded appropriately, have 
secondary containment and be 
inspected daily. 

If storing non-RCRA wastes, 
RCRA requirements may still be 
relevant and appropriate. 

Storage of 

auxiliary 

wastes 

RCRA: 40 

CFR Part 264 
Subpart 1 
(or state 
equivalent) 

Regulation covers 
storage of waste 
materials 
generated. 

Potential hazardous wastes remaining 
after treatment (i.e., spent biocarrier, 
etc.) must be labeled as hazardous 
waste and stored in containers in good 
condition. Containers should be stored 
in a designated storage area and 
storage should not exceed 90 days 
unless a storage permit is obtained. 

Applicable for RCRA wastes; 
relevant and appropriate for 
non-RCRA wastes. 

Determination 
of cleanup 
standards 

SARA: 

Section 
121(d)(2)(H); 
SDWA: 40 

CFR Part 141 

Standards that 
apply to surface & 
groundwater 
sources that may 
be used as drinking 
water. 

Applicable and appropriate for the 
EcoMat BDN Process used in projects 
treating groundwater for use as 
drinking water. 

Remedial actions of surface and 
groundwater are required to 
meet MCLGs or MCLs 

established under SDWA. 


RCRA: 40 

CFR Part 262 

Standards that 
pertain to 

generators of 
hazardous waste. 

Waste generated by the EcoMat 
process which may be hazardous is 
limited to spent carbon, well purge 
water, spent media or biocarriers, 
clarification/filtration residual wastes, 
and decontamination wastes. 

Generators must dispose of 
wastes at facilities that are 
permitted to handle the waste. 
Generators must obtain an EPA 

ID number prior to waste 
disposal. 

Waste disposal 

CWA: 40 CFR 
Parts 403 
and/or 122 
and 125 

Standards for 
discharge of 
wastewater to a 
POTW or to a 
navigable 
waterway. 

Applicable and appropriate for well 
purge water and decontamination 
wastewater generated from process. 

Discharge of wastewater to a 
POTW must meet pre-treatment 
standards; discharges to a 
navigable waterway must be 
permitted under NPDES. 


11 




















2.8.2 Resource Conservation and Recovery Act 
(RCRA) ■ 

RCRA, an amendment to the Solid Waste Disposal Act 
(SWDA), is the primary federal legislation governing 
hazardous waste activities. It was passed in 1976 to 
address the problem of how to safely dispose of the 
enormous volume of municipal and industrial solid waste 
generated annually. Subtitle C of RCRA contains 
requirements for generation, transport, treatment, storage, 
and disposal of hazardous waste, most of which are also 
applicable to CERCLA activities. The Hazardous and Solid 
Waste Amendments (HSWA) of 1984 greatly expanded the 
scope and requirements of RCRA. RCRA regulations 
define hazardous wastes and regulate their transport, 
treatment, storage, and disposal. These regulations are 
only applicable to the EcoMat Biological Denitrification and 
Post-Treatment processes if RCRA defined hazardous 
wastes are present. 

Hazardous wastes that may be present include the 
aqueous waste to be treated, spent media or biocarriers 
from each of the reactors, and the residual wastes 
generated from any process included in the post-treatment 
system, such as clarification and filtration. If wastes are 
determined to be hazardous according to RCRA (either 
because of a characteristic or a listing carried by the 
waste), essentially all RCRA requirements regarding the 
management and disposal of this hazardous waste will 
need to be addressed by the remedial managers. Wastes 
defined as hazardous under RCRA include characteristic 
and listed wastes. 

Criteria for identifying characteristic hazardous wastes are 
included in 40 CFR Part 261 Subpart C. Listed wastes 
from specific and nonspecific industrial sources, off- 
specification products, spill cleanups, and other industrial 
sources are itemized in 40 CFR Part 261 Subpart D. 
RCRA regulations do not apply to sites where RCRA- 
defined wastes are not present. 

Unless they are specifically delisted through delisting 
procedures, hazardous wastes listed in 40 CFR Part 261 
Subpart D currently remain listed wastes regardless of the 
treatment they may undergo and regardless of the final 
contamination levels in the resulting effluent streams and 
residues. This implies that even after remediation, treated 
wastes are still classified as hazardous wastes because 
the pre-treatment material was a listed waste. 

For generation of any hazardous waste, the site 
responsible party must obtain an EPA identification 
number. Other applicable RCRA requirements may 
include a Uniform Hazardous Waste Manifest (if the waste 
is transported off-site), restrictions on placing the waste in 
land disposal units, time limits on accumulating waste, and 
permits for storing the waste. 

Requirements for corrective action at RCRA-regulated 


facilities are provided in 40 CFR Part 264, Subpart F 
(promulgated) and Subpart S. These subparts also 
generally apply to remediation at Superfund sites. 
Subparts F and S include requirements for initiating and 
conducting RCRA corrective action, remediating 
groundwater, and ensuring that corrective actions comply 
with other environmental regulations. Subpart S also 
details conditions under which particular RCRA 
requirements may be waived fortemporary treatment units 
operating at corrective action sites and provides 
information regarding requirements for modifying permits 
to adequately describe the subject treatment unit. 

2.8.3 Clean Air Act (CAA) 

The CAA establishes national primary and secondary 
ambient air quality standards for sulfur oxides, particulate 
matter, carbon monoxide, ozone, nitrogen dioxide, and 
lead. It also limits the emission of 189 listed hazardous 
pollutants such as vinyl chloride, arsenic, asbestos and 
benzene. States are responsible for enforcing the CAA. 
To assist in this, Air Quality Control Regions (AQCR) were 
established. Allowable emission limits are determined by 
the AQCR, or its sub-unit, the Air Quality Management 
District (AQMD). These emission limits are based on 
whether or not the region is currently within attainment for 
National Ambient Air Quality Standards (NAAQS). 

The CAA requires that treatment, storage, and disposal 
facilities comply with primary and secondary ambient air 
quality standards. Emissions from post-treatment systems 
associated with EcoMat’s Biological BDN may need to 
meet current air quality standards. For example, the 
ozonation system may be regulated by state or local 
agencies. Also, State air quality standards may require 
additional measures to prevent emissions, including 
requirements to obtain permits to install and operate 
processes (e.g., air strippers for control of VOCs). 

2.8.4 Clean Water Act (CWA) 

The objective of the Clean Water Act is to restore and 
maintain the chemical, physical and biological integrity of 
the nation's waters by establishing federal, state, and local 
discharge standards. If treated water is discharged to 
surface water bodies or Publicly Owned Treatment Works 
(POTW), CWA regulations will apply. A facility desiring to 
discharge water to a navigable waterway must apply for a 
permit under the National Pollutant Discharge Elimination 
System (NPDES). When a NPDES permit is issued, it 
includes waste discharge requirements. Discharges to 
POTWs also must comply with general pretreatment 
regulations outlined in 40 CFR Part 403, as well as other 
applicable state and local administrative and substantive 
requirements. 

The demonstration did have a variety of available options 
for disposal of the water. These options included 


12 



discharge 1) to a 1 000 gallon septic system, 2) to a nearby 
down gradient drainage network, 3) back down PWS Well 
#, and 4) into the ground down gradient of PWS Well #1. 
After careful review, option #1 was selected as the most 
viable. 

Treated effluent from the SITE demonstration was 
discharged to an on-site 1000 gallon septic system at a 
rate of approximately 7,200 gallons per day. Permission 
for septic system installation and discharge to the system 
was required by Doniphan County, KS. The county 
required the completion of a Sewage Facility 
Application/Permit. Approval for discharge to the septic 
system was granted by the KDHE. 

The only listed option that would have been regulated 
underthe CWA and required a NPDES permit would have 
been discharge to a nearby down gradient drainage 
network. It should be noted that depending on the levels 
of contaminantsand permit limitations, additional treatment 
may be required prior to discharge. 

2.8.5 Safe Drinking Water Act (SDWA) 

The SDWAof 1974, as mostrecently amended bythe Safe 
Drinking Water Amendments of 1986, requires the EPA to 
establish regulations to protect human health from 
contaminants in drinking water. The legislation authorized 
national drinking water standards and a joint federal-state 
system for ensuring compliance with these standards. 

The National Primary Drinking Water Standards (NPDWS) 
are found in 40 CFR Parts 141 through 149. Parts 144 and 
145 discuss requirements associated with the underground 
injection of contaminated water. If underground injection of 
wastewateris selected as adisposalmeans, approvalfrom 
EPA or the delegated state for constructing and operating 
a new underground injection well is required. 

Since the actual intent of the EcoMat BDN Process is to 
render the water as drinkable (i.e., reducing nitrate-N and 
nitrite-N to below their respective MCLs of 10 and 1 mg/I), 
in most cases treated effluent would be discharged directly 
into the community water system. For example, the treated 
effluent could be routed to 1) a water supply tank, 2) to an 
existing drinking water treatment system, or 3) a 
distribution system. If the final effluent of the system were 
to be used for drinking purposes while providing no 
additional treatment, the quality of the water would need to 
meet NPDWS. 

During the demonstration elevated concentrations of both 
heterotrophic bacteria and methanol were found in the 
treated effluent. Heterotrophic bacteria, which are 
measured to determine how effective treatment is at 
controlling microorganisms, have no reported health 
effects. 40 CFR 141.72 of the NPDWS states that in lieu 
of measuring the residual disinfectant concentration in the 
distribution system, heterotrophic bacteria, as measured by 


the heterotrophic plate count, may be performed. If 
heterotrophic bacteria concentrations are found above 
500/100 ml in the distribution system, the minimum residual 
disinfectant concentration is not in compliance with the 
NPDWS. There are no standards or health advisories for 
methanol in the NPDWS. The agency delegated for 
enforcement of the NPDWS would need to be notified of 
these elevated concentrations well before supplying this 
water to customers. 

The NPDWS also have turbidity standards which must be 
met. A standard of 1.0 turbidity unit (NTU), as determined 
by a monthly average must be met. During the 
demonstration the calculated averages for three of the four 
sampling events were above the 1.0 NTU limit. 

2.8.6 Occupational Safety and Health Administration 
(OSHA) Requirements 

CERCLA remedial actions and RCRA corrective actions 
must be performed in accordance with the OSHA 
requirements detailed in 20 CFR Parts 1900 through 1926, 
especially Part 1910.120, which provides for the health and 
safety of workers at hazardous waste sites. On-site 
construction activities at Superfund or RCRA corrective 
action sites must be performed in accordance with Part 
1926 of OSHA, which describes safety and health 
regulations for construction sites. State OSHA 
requirements, which may be significantly stricter than 
federal standards, must also be met. 

If working at a hazardous waste site, all personnel involved 
with the construction and operation of the EcoMat BDN 
treatment process are required to have completed an 
OSHA training course and must be familiar with all OSHA 
requirements relevant to hazardous waste sites. Workers 
on hazardous waste sites must also be enrolled in a 
medical monitoring program. The elements of any 
acceptable program must include: (1) a health history, (2) 
an initial exam before hazardous waste work starts to 
establish fitness for duty and as a medical baseline, (3) 
periodic examinations (usually annual) to determine 
whether changes due toexposure may have occurred and 
to ensure continued fitness for the job, (4) appropriate 
medical examinations after a suspected or known 
overexposure, and (5) an examination at termination. 

For most sites, minimum PPE for workers will include 
gloves, hard hats, steel-toe boots, and Tyvek® coveralls. 
Depending on contaminant types and concentrations, 
additional PPE may be required, including the use of air 
purifying respirators or supplied air. Noise levels are not 
expected to be high, except during well installation which 
will involve the operation of drilling equipment. During 
these activities, noise levels should be monitored to ensure 
that workers are not exposed to noise levels above a time- 
weighted average of 85 decibels over an eight-hour day. 
If noise levels increase above this limit, then workers will 


13 



community, but this will depend on proximity to the 
treatment site. 


be required to wear hearing protection. The levels of noise 
anticipated are not expected to adversely affect the 



Section 3.0 
Economic Analysis 


3.1 Introduction 

The purpose of this economic analysis is to estimate costs 
(not including profits) for commercial treatment of 
groundwater contaminated with elevated levels of nitrate 
utilizing the EcoMat BDN Process. 

The treatment system evaluated at Bendena was operated 
in an approximate range of 3-8 gpm during the SITE 
demonstration. This pilot-scale treatment system is 
considered by EcoMat to have an extremely low capacity 
for producing drinking water. The full-scale systems that 
EcoMat plans to design, own and operate for drinking 
water applications are 10 to 50 times the size of the pilot 
unit used at Bendena. Therefore, this analysis will present 
a cost estimate based on a 100 gpm system. 

The costs associated with implementing the EcoMat 
designed and operated process have been broken down 
into 12 cost categories that reflect typical cleanup activities 
at Superfund sites. They include: 

(1) Site Preparation 

(2) Permitting and Regulatory Activities 

(3) Capital Equipment 

(4) Start-up and Fixed 

(5) Labor 

(6) Consumables and Supplies 

(7) Utilities 

(8) Effluent Treatment and Disposal 

(9) Residuals Shipping, & Disposal 

(10) Analytical Services 

(11) Maintenance and Modifications 

(12) Demobilization 

To reasonably estimate costs for the technology, some 
basic assumptions have been made regarding the overall 
size of the reactors, treatment flow rate, level of nitrate 
contamination, presence ofothercontaminants (otherthan 
nitrate), treatment duration, and the level of post-treatment 
required to meet standard Safe Drinking Water criteria for 
general parameters. 


The EcoMat BDN Process is ex-situ and is designed to 
operate on a continual pump and treat mode. Standard 
sized tanks are used as the reactors and holding tanks. 
The only specialized mechanical equipment used is the 
patented mixing apparatus that is fitted into the standard¬ 
sized reactor tank. EcoMat prefers to install and own their 
treatment systems, and then service the systems with local 
contractors. EcoMat would then bill monthly for the 
service. However, this cost estimate assumes the site 
owner will purchase the treatment system and pay for 
setup, monitoring, and maintenance. 

Table 3-1 presents a categorical breakdown of estimated 
costs for the one year’s treatment of groundwater, using a 
100 gpm BDN system, atan assumed online factor of 80% 
(42 million gallons treated annually). Table 3-2 projects the 
first year cost estimates to approximate costs forthe same 
100 gpm capacity and at the same assumed on-line factor 
of 80% for multi-year treatment (e.g., 5,10, and 15 years). 
Figure 3-1 graphically illustrates th*e percentage of total 
costthateach ofthe twelve cost components comprise, for 
each treatment scenario. 

As with all cost estimates, caveats may be applied to 
specific cost values based on associated factors, issues, 
and assumptions. The major factors that can affect 
estimated costs are discussed in subsection 3.3. The 
issues and assumptions made regarding the specific 
treatment system used for this economic analysis are 
incorporated into the cost estimate. They are discussed in 
subsection 3.4. 

The basis for costing each of the individual 12 categories 
in Table 3.1 is discussed in detail in subsection 3.5. Much 
of the information presented in this subsection has been 
derived from observations made and experiences gained 
from the SITE demonstration that was conducted as four 
separate sampling events interspersed over an 
approximate 714 month period at the location of a former 
public water supply well in Bendena, Kansas. Other cost 
information has been acquired through subsequent 
discussions with EcoMat and by researching current 


15 



Table 3-1. Cost Estimates for Initial Year of 100 GPM BDN System, Online 80%. 


Cost Category 

Quantity 

Units 

Unit Cost 

$- I s ' Yr. 

$/Category 

1. Site Preparation 





$67,000 

Treatment System Delivery 

1 

Each 

$5,000 

$5,000 


Heated Building Enclosure 

1 

Each 

$60,000 

$60,000 


Utility Connections 

1 

Each 

$2,000 

$2,000 


2. Permitting & Regulatory Activities 





$30,000 

Permits 




$10,000 


Studies and Reports 




$20,000 


3. Capital Equipment 





$264,000 

Biodenitrification/Post-Treatment Systems 

1 

Each 

$250,000 

$250,000 


In-line Nitrate Analyzer (two cells) 

1 

Each 

$8,000 

$8,000 


In-line Dissolved Oxygen Meter 

1 

Each 

$2,000 

$2,000 


Portable Water Quality Instrumentation 

2 

Each 

$600 

$1,200 


Pressure Washer 

1 

Each 

$2,800 

$2,800 


4. Startup & Fixed (10% of Capital Equipment) 





$26,400 

5. Labor 





$69,900 

System Design 

100 

Hours 

$80 

$8,000 


Site Setup (EcoMat) 

40 

Hours 

$80 

$3,200 


(Contractor) 

400 

Hours 

$50 

$20,000 


Startup Testing (EcoMat) 

Performance Monitoring/Maintenance 

80 

Hours 

$80 

$6,400 


Remote Monitoring (EcoMat) 

210 

Hours 

$80 

$16,800 


On-site Monitoring (Contractor) 

310 

Hours 

$50 

$15,500 


6. Consumables and Supplies 





$5,580 

Methanol (99% + grade) 

1,200 

Gallons 

$0.65 

$780 


EcoLink Biocarrier 

0.2 

m 3 

$6,000 

$1,200 


Hypochlorite solution (for chlorination) 

600 

Gallons 

$6.00 

$3,600 


Post-Treatment Media 

NA 

NA 

NA 

NA 


7. Utilities 

175,000 

kW-hr 

$0.07 

$12,300 

$12,300 

8. Effluent Treatment & Disposal 

NA 

NA 

$0000.00 

$0000.00 


9. Residuals Shipping & Disposal 

NA 

NA 

$0000.00 

$0000.00 


10. Analytical Services 





$9,940 2 

Nitrate-N/Nitrite-N in Water 

27 

Each 

$15 

$405 


Methanol in Water 

27 

Each 

$100 

$2,700 


Fecal Coliform 

27 

Each 

$15 

$405 


Trihalomethanes 

27 

Each 

$150 

$4,050 


Sample Shipments 

54 

Each 

$30 

$1,620 


11. Maintenance & Modifications 

1 

Year 

$2,640 

$2,640 

$2,640 

12. Demobilization 

NA 

NA 

NA 

NA 


' Cost value rounded to two significant digits. 

2 Value increased to account for 10% QA samples. 



Total Initial 

Year Cost 1 

$490,000 


16 







Table 3-2. Cost Estimates for EcoMat’s BDN System for Multi-Year Treatment Scenarios. 


Cost Category 

Initial Year 

5 Years 

10 Years 

15 Years 

1. Site Preparation 2 

$67,000 

$67,000 

$67,000 

$67,000 

Treatment System Delivery 

$5,000 

$5,000 

$5,000 

$5,000 

Heated Building Enclosure 

$60,000 

$60,000 

$60,000 

$60,000 

Utility Connections 

$2,000 

$2,000 

$2,000 

$2,000 

2. Permitting/Regulatory Activities 2 

$30,000 

$30,000 

$30,000 

$30,000 

3. Capital Equipment 2 

$264,000 

$264,000 

$264,000 

$264,000 

4. Startup & Fixed 2 

$26,400 

$26,400 

$26,400 

$26,400 

5. Labor 

$69,900 

$225,000 

$418,200 

$612,200 

System Design 2 

$8,000 

$8,000 

$8,000 

$8,000 

Site Setup 2 

$23,200 

$23,200 

$23,200 

$23,200 

Startup Testing 3 

$6,400 

$32,000 

$64,000 

$96,000 

Perf. Monitoring/Maintenance 

$32,300 

$162,000 

$323,000 

$485,000 

6. Consumables & Supplies 

$5,580 

$27,900 

$55,800 

$83,700 

Methanol 

$780 

$3,900 

$7,800 

$11,700 

Hypochlorite Solution 

$3,600 

$18,000 

$36,000 

$54,000 

EcoLink Biocarrier 

$1,200 

$6,000 

$12,000 

$18,000 

Post-Treatment Media 

$000.00 

$000.00 

$000.00 

$000.00 

7. Utilities (Electricity) 

$12,300 

$61,500 

$123,000 

$184,500 

8. Effluent Treatment & Disposal 

NA 

NA 

NA 

NA 

9. Residuals Shipping & Disposal 

NA 

NA 

NA 

NA 

10. Analytical Services 

$9,940 

$15,900 

$23,500 

$31,100 

Nitrate in water 

$405 

$645 

$945 

$1,250 

Methanol in water 

$2,700 

$4,300 

$6,300 

$8,300 

Fecal Coliform 

$405 

$705 

$1,220 

$1,670 

Trihalomethanes 

$4,050 

$6,450 

$9,450 

$12,500 

QA samples (10%) 

$756 

$1,210 

$1,790 

$2,370 

Sample Shipments 

$1,620 

$2,580 

$3,780 

$4,980 

11. Maintenance & Modifications 

$2,640 

$13,200 

$26,400 

$39,600 

12. Demobilization 

$000,000 

$000,000 

$000,000 

$000,000 

TOTAL COSTS ' 

$490,000 

$730,000 

$1,000,000 

$1,300,000 


1 Total costs have been rounded to two significant digits. 

2 Designates a one time cost incurred for all scenarios. 

3 Startup testing is assumed to be repeated once per year. 


17 










Total Treatment Costs, Dollars 


o 

o 

o 

O 

O 

o 

o 

o 

o 

o 

o 

o_ 

o 

o 

o 

o’ 

o 

CD 

o" 

IT) 

o' 

o 

CO 

o' 

IT) 

in 



<u 

a 



sje//oc7 sjsoo jL/suyjesjj^ /ejo_i 


Figure 3-1. Cost Distributions - EcoMat Biodenitrification Multi-Year Treatment Scenarios. 


18 















































estimates for specific cost items related to the technology. 
Certain actual or potential costs were omitted because site- 
specific engineering aspects beyond the scope of this SITE 
Demonstration project would be required. Certain other 
functions were assumed to be the obligation of the 
responsible parties and/or site owners. Although these 
costs are also not included in the estimate, they are still 
shown as line items on Tables 3.1 and 3.2 to emphasize 
that those costs need to be accounted for. 

It should be emphasized that the cost figures provided in 
this section are “order-of-magnitude" estimates, generally 
+ 50% / -30%. 

3.2 Conclusions 

The majority of the information for the costs (as well as 
some actual costs) to treat groundwater using the EcoMat 
BDN System at a flow rate of 100 gpm were provided by 
EcoMat. These estimates, along with other conclusions of 
the economic analysis, are presented below: 

(1) For a 100 gpm system, the estimated cost to treat 

nitrate-contaminated groundwater over a one year 
period is $490,000, or approximately $0.012/gal. 
The cost over 5, 10,or 15 years is estimated to 
increase to approximately $730,000 ($0.0034/gal.); 
$1,000,000 ($0.0024/gal.) and $1,300,000 

($0.002/gal.), respectively. 

(2) The largest cost components for the one-year 
application of a 100 gpm EcoMat BDN system are 
capital equipment (54%), labor (14%), and site 
preparation (14%); accounting forover 80% of the 
total cost. As the treatment duration increases 
over time, the impact of capital equipment and site 
preparation diminish considerably. Shortly 
following five years of treatment, labor becomes 
the dominant cost component and the impact of 
consumables and supplies becomes more 
significant. 

(3) The cost of implementing the EcoMat 
Biodenitrification System may be less or more 
expensive than the estimate given in this economic 
analysis depending on several factors. If water 
recovery wells are not already present at the site, 
their installation would be a significant added cost 
to the site owner, especially if the water source is 
deep (these costs are not directly associated with 
the EcoMat treatment process and thus have not 
been included in the estimate). Other factors 
include, but are not limited to, the nitrate 
concentration in the water and the presence of 
other contaminants that would require increased 
post-treatment or pretreatment. 


3.3 Factors Affecting Estimated Cost 

There are a number of factors that could affect the cost of 
treatment of nitrate-contaminated groundwater using an ex 
situ bioremediation treatment technology. An important 
factor for initial consideration is the ability to supply 
contaminated water at an economically viable flow rate 
(which is dependent on aquifer characteristics). Other 
important factors include, but are not limited to, the inlet 
nitrate concentration (as measured as nitrate-N), the 
presence of other contaminants in the inlet water, and the 
level of pre-or post-treatment required. 

The aquiferyield will affect the size and numberof pumping 
wells required to attain sufficient flow rate to allow 
treatment to be econom ically feasible. For aquifers that are 
capable of yielding high flow rates, the numberof wells that 
are required to be installed and the depth at which they 
must be screened can significantly impact startup costs, 
but this would affect any system. 

3.4 Issues and Assumptions 

This section summarizes the major issues and 
assumptions used toestimate the cost of implementing the 
EcoMat BDN Process at full-scale. In general, the 
assumptions are based on information provided by 
EcoMat and observations made during the demonstration. 

3.4.1 Site Characteristics 

The site characteristics used for this economic analysis 
are considered to be significantly differentfrom those found 
at the Bendena site. The Bendena demonstration site 
consisted of a former railroad well constructed in the early 
1900's. Pre-demonstration pump testing ofthis well at just 
20 gpm over a 5-day period depleted nearly 30 percent of 
the well volume. Thus, the aquifer recharge would not be 
sufficient for adequately supplying a 100 gpm treatment 
system. Also, nitrate levels in the well water were 
measured as high as 100 ppm. Such levels of nitrate in a 
well are uncommon and EcoMat has costed their treatment 
system to be contingent on an inlet nitrate level of 20 mg/I. 

For the purposes of this analysis, there are three major 
assumptions that have been made regarding site 
characteristics: 1) the aquifer being treated is capable of 
supplying groundwater to one or more wells at a rate equal 
to or greaterthan 100 gpm for an extended time period; 2) 
no additional wells are required, and 3) that nitrate-N levels 
will be consistently above the regulatory limit of 10 mg/I but 
will not exceed 20 mg/I. 

3.4.2 Design and Performance Factors 

Design and performance factors would include designing 
the properly-sized treatment system and process 
parameters to adequately treat nitrate-contaminated 


19 



groundwater at a rate of 100 gpm. If need be, a 
groundwater recovery system may also need to be 
designed and would include locating and installing 
groundwaterrecovery wells and the associated pumps and 
piping to route the inlet water to the treatment system. For 
this cost estimate an assumption is made that sufficient 
groundwaterrecovery wells and piping are already present 
at the site. 

The developer (EcoMat)designs the properly-sized system 
anticipated fora particular site. Once designed the system 
components are manufactured or purchased off-site, 
usually from one or more vendors. The components are 
then shipped from the plant(s) to the site location, where 
EcoMat assembles the system. 

With respect to the pilot-scale unit used at Bendena, 
EcoMat has indicated that a 100 gpm system would be 
scaled-up in physical size by a factor of between two and 
three times that of the pilot unit. 

3.4.3 Financial Assumptions 

All costs are presented in Year 2001 U.S. dollars without 
accounting for interest rates, inflation, or the time value of 
money. Insurance and taxes are assumed to be fixed 
costs lumped into “Startup and Fixed Costs” (see 
subsection 3.5.4). Any licensing fees passed on by the 
developer, for using the EcoMat patented mixed reactor 
and implementing technology-specific functions, would be 
considered profit. Therefore, those fees are not included 
in the cost estimate. 

3.5 Basis for Economic Analysis 

The 12 cost categories reflect typical clean-up activities 
encountered at Superfund sites. In this section, each of 
these activities will be defined and discussed. Combined, 
these 12 cost categories form the basis for the detailed 
estimated costs presented in Tables 3-1 and 3-2. The 
labor costs that are continually repeated for each scenario 
are grouped into two labor categories, one category for 
developer labor (i.e., EcoMat) and one category for 
developer contractor labor (see subsection 3.5.5). 

3.5.1 Site Preparation 

Site preparation for implementing the EcoMat BDN system 
technology can be subdivided into three distinct phases. 
These include the initial design of the treatment (system 
design), shipping and assembly of the designed system 
(site setup) and conducting initial shakedown/recycle 
testing. The first two phases are one time occurrences. The 
shakedown and recycle phase may have to be repeated if 
the system stops operating for a substantial period of time 
during the treatment process. 

All three of these phases are discussed in the following 


subsections. However, the majority of the costs associated 
with site preparation is labor (labor costs are presented in 
subsection 3.5.5). Therefore, the only costs discussed in 
this subsection are non-labor costs associated with site 
setup phase (see 3.5.1.2). The total non-labor cost of site 
preparation for the beginning operation of the system is 
estimated to be approximately $67,000, which would be a 
one time cost. 

3.5.1.1 System Design 

System design consists of obtaining the anticipated 
contaminant range from the prospective customer and then 
selecting the proper sized system components necessary 
for treating that influent at a specified flow rate. EcoMat 
does not conduct treatability testing on the water matrix 
(i.e., influent); however, they do have small reactors that 
could be used for such a purpose. Generally speaking, the 
system design does notinclude the means forpumping the 
water matrix from its source to the BDN system. 

EcoMat has indicated thatthe design of a 100 gpm system 
would not radically change from the design of the pilot unit 
used at Bendena, however the scale-up factor would be 
between two and three. Therefore the deoxygenating tank 
(R1) would have an approximate capacity of 2,600 gallons 
and the EcoMat Reactor (R2) would be on the order of 5 
cubic meters (the R2 unit at Bendena was 2 cubic meters). 
The cost of system design has been estimated by EcoMat 
to correlate to approximately 100 hours (see subsection 
3.5.5 - Labor). 

3.5.1.2 Site Setup 

The second phase of site preparation is site setup. This 
phase includes shipping the treatment system components 
from one or more of EcoMat’s suppliers to the site. The 
costs of shipping will vary depending on location and 
distance the site is from the supplier(s). EcoMat roughly 
estimates shipping costs at 2% of the treatment system 
capital cost. For a 100 gpm treatment unit, this would be 
approximately $5,000 (see subsection 3.5.3 for capital 
costs). 

Once at the site the entire treatment system is normally 
housed in a shed or building that provides security and 
temperature control. Therefore, if an appropriate existing 
structure does not exist at the site, one has to be 
assembled or built. EcoMat has estimated that a building 
twice the size of the Bendena shed would be required to 
accommodate a 100 gpm system. It is feasible to install a 
system outside, which may be necessary for even larger 
systems. In such instances, heat tracing would be installed 
to provide temperature control where needed. 

At the Bendena site, the KDHE provided for the 20 ft. x 15 
ft. building and all associated utility hookups at an 
approximate cost of $40,000 (which included construction 


20 



labor costs). The cost of a structure about twice that size 
(i.e., 40 ft. x 30 ft.), not including utility hookups, is 
estimated at approximately $60,000. 

At the Bendena site, electrical hookups, communications, 
and water supply were also provided by the KDHE and 
incorporated into the total cost estimate for the shed. 
Electrical power is required for operating pumps, control 
panels, etc. for the system; lighting, etc. A water hookup 
is needed for power washing equipment components (e.g., 
filters, etc.). For this cost estimate, utility hookups are 
estimated to be a one time charge of $2,000. 

It is assumed that the site used for this cost estimate is 
secured and cannot be easily vandalized. The treatment 
system itself would, in most cases, be installed within a 
secured building, as previously discussed. If security 
became an issue with a larger outdoor system, then a 
fence would need to be erected. Assuming no costs for 
security, the total site setup costs for initiating the activities 
are estimated to total approximately $67,000. This cost 
value represents the total non-labor cost estimated for the 
Site Preparation category. 

3.5.1.3 Shakedown and Recycle 

Once the fulltreatment system has been assembled, there 
is a period of time necessary to acclimate the microbial 
colony to the biocarrier(s), and the inlet water, make 
adjustments to methanol feed rates, and check operation 
of system components. Once this steady-state is reached 
the system can continually operate effectively as long as 
there are no significant shutdowns. 

The overwhelming majority of the cost associated with the 
shakedown and recycle process is labor, which is 
discussed in subsection 3.5.5. The cost of consumables 
specifically associated with conducting shakedown and 
recycle activities are negligible with respect to total annual 
consumables (consumable costs are discussed in 
subsection 3.5.6). 

3.5.2 Permitting and Regulatory Requirements 

Several types of permits may be required for implementing 
a full-scale remediation. The types of permits required will 
be dependent on the type and concentration of the 
contamination, the regulations covering the specific 
location, and the site’s proximity to residential 
neighborhoods. 

Atthe Bendenasite, treated waterwas discharged to a 300 
foot long, 1,000 gallon capacity lateral septic system 
purchased and installed forthe demonstration. The KDHE 
acquired the necessary permits for discharging the treated 
water to the septic system located in an adjacent field in 
this manner. Although, ozone treatment and an air stripper 
were used during portions of the demonstration, a permit 
was not required. 


The non-analytical costs incurred for ultimately receiving 
approval from the regulatory agency to install the treatment 
system are included under the Permitting and Regulatory 
Activities category. These costs would include the 
preparation of site characterization reports that establish a 
baseline for the site contamination, the design feasibility 
study for the pilot system, potential meetings with 
regulators for discussing comments and supplying other 
related documentation, and for acquiring approval for 
installing and implementing the treatment. 

Based on pastexperience, permitting feesforimplementing 
the full-scale treatment system are assumed to be about 
$10,000. It should be noted that actual permitting fees are 
usually waived for government-conducted research type 
projects (e.g., SITE Demonstrations). 

Depending upon the classification of the site, certain RCRA 
requirements may have to be satisfied as well. If the site 
is an active Superfund site, it is possible that the 
technology could be implemented under the umbrella of 
existing permits and plans held by the site owner or other 
responsible party. Certain regions or states have more 
rigorous environmental policies that may result in higher 
costs forpermits and verification of treatment performance. 
Added costs may result from investigating all of the 
regulations and policies for the location of the site, and for 
conducting a historical background check for fully 
understanding the scope of the contamination. From 
previous experiences, the associated cost with these 
studies and reports is estimated to be $20,000. 

The total cost of all necessary permitting and other 
regulatory requirements is estimated to be approximately 
$30,000. 

3.5.3 Capital Equipment 

Most of the capital equipment cost data directly associated 
with the BDN and post-treatment system have been 
supplied by EcoMat. Specific capital equipment associated 
with their system includes high density polyethylene tanks, 
high capacity pumps, electronic control systems, a 
patented mixing apparatus, system piping and valves, 
rotometers, and various off-the-shelf post-treatment units. 
Some of the monitoring equipment costs are based on the 
SITE Program's experience during the demonstration and 
from other similar products. It is assumed that all 
equipment parts will be a one time purchase and will 
have no salvage value at the end of the project. 

EcoMat has provided an approximate lump sum cost 
estimate of $250,000 for a 100 gpm treatment system 
capable of treating a water matrix having nitrate levels of 
20 mg/I. This value does not include the installation of 
groundwater wells, groundwater pumps, or piping 
installation required to supply inlet water to the treatment 
system (at the Bendena site the groundwater supply 
delivery system consisted of a single submersible pump 


21 



that supplied the BDN system with groundwater at flow 
rates varying between 3 and 8 gpm). The $250,000 value 
also does not include costs for disassembly, shipping and 
reclaiming system components. 

In addition to the main components of the EcoMat BDN and 
post- treatment systems, in-line monitoring equipment 
would be an additional capital cost. The most important 
monitoring instrumentation required for a full-scale system 
would be an in-line nitrate analyzerequipped with two cells; 
one for monitoring inlet water nitrate levels and one for 
monitoring either post BDN or final effluent nitrate levels. 
The estimated cost for a direct read nitrate analyzer is 
$ 8 , 000 . 

Dissolved oxygen is another important parameter that 
requires close monitoring, as evidenced during the 
demonstration. Since the time of the demonstration, 
EcoMat has incorporated a dissolved oxygen monitoring 
unit into their system to immediately identify irregularities in 
DO. A microprocessor-based DO meter installed within the 
BDN system is estimated to cost $2,000. Other portable 
instrumentation required formonitoring parameters such as 
pH, temperature, and turbidity are estimated to collectively 
cost about $1,200. 

Although an industrial pressure washer could be rented on 
an as-need-basis, it will be assumed that a dedicated 
pressure washer would be purchased for EcoMat’s full- 
scale unit. This would allow for quicker response to any 
periodic clogging of filters and reactor screens (which 
occurred during the demonstration) and the cost would be 
relatively minor with respect to the cost of the treatment 
system itself or renting the equipment over several years. 
A combination steam cleaner/pressure washer is estimated 
to cost roughly $2,800. 

The total cost of all of the necessary capital equipment for 
a full-scale 100 gpm system is estimated to be 
approximately $264,000. 

3.5.4 Startup and Fixed Costs 

From past experience, the fixed costs for this economic 
analysis are assumed to include only insurance and taxes. 
They are estimated as 10 percent of the total capital 
equipment, or $26,400. 

3.5.5 Labor 

Included in this subsection are the core labor costs that are 
directly associated with the EcoMat BDN System. These 
costs comprise the bulk of the labor required for the full 
implementation of the technology. It is assumed for this 
cost analysis that the treatment system will be fully 
automated and will operate continuously without major 
interruption at the designed flow rate. Non-core labor 
costs, associated with periodic system adjustments (i.e., 
chemical adjustments), regulatory sampling requirements, 


maintenance activities, and site restoration, are discussed 
in subsections 3.5.10, 3.5.11 and 3.5.12, respectively. 

For the purchased EcoMat treatment system, assembly is 
a labor intensive operation consisting of unloading 
equipment from trucks and trailers, as well as actual 
assembly. EcoMat will have significant hands-on 
involvement during the site setup phase of the project and 
early stages of a field project to ensure proper assembly 
and startup of their technology. EcoMat's labor hours, as 
specified in Tables 3-1 and 3-2, would include overseeing 
and training local contractors on the operation of the 
system and making the proper adjustments to the system 
during the shakedown and recycle operation. Once the 
system is acclimated and operating ata steady state, labor 
should become minimal. 

The hourly labor rates presented in this subsection are 
loaded, which means they include base salary, benefits, 
overhead, and general and administrative (G&A) expenses. 
Travel, per diem, and standard vehicle rental have not 
been included in these figures. The labortasks have been 
broken down into four subcategories, each representing 
distinct phases of technology implementation. They 
include 1) System Design 2) Site Setup; 3) Startup Testing; 
and 3) Performance Monitoring & Maintenance. 

3.5.5.1 System Design 

System design consists of obtaining the anticipated 
contaminantrangefrom the prospective customerand then 
selecting the properly-sized system components necessary 
for treating that influent at a specified flow rate. Specific 
tasks may include preparation of design parameters and 
detailed process flow schematics (including piping 
designs), logistics for procuring the specific system 
components, and calculating feed rates for methanol 
solution and other additives. EcoMat has estimated 
system design labor at 100 hours. Assuming a loaded rate 
of $80/hr for an EcoMat process design engineer (or 
comparable professional) to conduct this task, labor for 
system design is estimated at $8,000. 

3.5.5.2 Site Setup 

Site setup includes labor costs that are not already 
included in the system design. These costs would 
therefore include the labor to assemble the system 
com ponents and associated monitoring equipment once at 
the site; organization and storage of the initial year's 
supplies (e.g., methanol, filter cartridges, etc.); and 
arranging for and overseeing the utility hookups. Due to 
the importance of these initial activities, it is assumed that 
the developer will be on-site to direct and assist 
subcontracted personnel. 

It is assumed that the developer will supply one senior level 
process engineer, billing out at an estimated $80/hour, to 


22 



perform oversight duties. It is also assumed that the 
developer will contract out for supplying a local field team 
consisting of two technical staff personnel. The average 
hourly loaded rate for these two individuals is estimated to 
be $50/hour. To complete the aforementioned tasks for a 
100 gpm system, EcoMat has estimated 40 hours of their 
time ($3,200) and 400 contractor hours ($20,000). 
Therefore, total labor for the site setup phase has been 
estimated at approximately $23,200. 

3.5.5.3 Startup Testing 

The EcoMat process requires a period of time for 
developing the necessary biological growth on the 
biocarrier in the EcoMat Reactor under a full recycle mode. 
EcoMat refers to this startup testing phase as the 
“Shakedown and Recycle Operation.” The shakedown and 
recycle operation for the SITE demonstration took 
approximately eightweeks. EcoMat has indicated thatthis 
process can be completed in about half of that time under 
closer control and that the time period does not vary 
significantly with the size of the project. They have 
estimated 80 hours of laborforcompleting this task, which 
at an $80/hr rate would total $6,400. The shakedown and 
recycle mode must be repeated if the system goes down 
for an extended period to re-acclimate the microorganisms 
(this was necessary during the demonstration). For this 
cost it will be assumed that system startup will have to be 
repeated at least once annually. Thus the $6,400 labor 
cost will be incurred each and every year of operation. 

3.5.5.4 Performance Monitoring & Maintenance 

Although the full-scale system is assumed to be fitted with 
an on-line nitrate/nitrite analyzer and other automated 
systems (i.e., for metering the proper amount of methanol 
solution, chlorination, etc.), the full-scale system would still 
require both remote (off-site) and on-site monitoring to 
ensure reliable and consistent system performance. 

Off-site monitoring of the full-scale treatment system would 
at minimum be capable of continuously tracking inlet and 
effluent nitrate and nitrite levels, dissolved oxygen levels, 
and system disruptions as indicated by the control panel 
alarms (i.e., high tank level alarms, pump malfunctions, 
high dissolved oxygen levels, etc.). 

Actual on-site observation would also be necessary, as 
would routine maintenance site visits. Observing the 
system is required to visualize biocarrier suspension in the 
EcoMat reactor. Periodic maintenance of the system is 
required forfilter backflushing, adjusting methanol solution 
feed rate, washing the bioballs in the deoxygenating 
reactor, replenishing hypochlorite solution supply, etc. 

With respect to a 100 gpm system, EcoMat has estimated 
their off-site monitoring labor at four hours per week and 
contracted on-site labor at six hours per week. Assuming 


the same labor rates of $80/hr and $50/hr for EcoMat and 
contractor labor, respectively, the weekly labor cost for 
performance monitoring is estimated at $620/week. This 
weekly cost would equate to $32,300 annually. 

Total labor costs for the first year of treatment operation 
would total approximately $69,900. Although labor 
comprises only about 14% of the total first year treatment 
costs, laboris projected to become the highest annualcost 
category over time. Labor costs at five, ten and 15-years 
of operation are estimated to comprise roughly 30%, 42%, 
and 47% of the total annual costs, respectively. 

3.5.6 Consumables & Supplies 

Due to the higher initial capital costs, consumables and 
supplies comprise a relatively small initial year cost 
component (i.e., slightly more than 1 % of the first year total 
cost) for the EcoMat system. As the capital cost impact 
diminishes over time, the consumables and supplies costs 
gradually increase in significance. Potential consumables 
and supplies costs for the EcoMat Biodenitrification 
process can be associated with four subcategories: 1) 
Nutrients and growth substrate; 2) Biocarrier media; 3) 
Post-treatment consumables; and 4) Equipment rentals. 

3.5.6.1 Nutrients and Growth Substrate 

Growth substrate includes any consumable supply that is 
added to the BDN system to specifically sustain or 
enhance the viability of microbes used to degrade nitrate 
and nitrite. The primary substrate is a 50% aqueous 
methanol solution that is added to both the de-oxygenating 
reactor tank and the EcoMat reactor. 

During the demonstration, the methanol solution feed rate 
roughly ranged from 7-10 liters per day. EcoMat has 
indicated that three times that feed rate would be required 
for a 100 gpm system. Therefore, a high range of 30 
liters/day of “solution” would provide a conservative 
estimate. That daily feed rate would total approximately 
8,800 liters of “solution” consumed per year for a system 
on-line 80%. Thus, approximately 4,400 liters (about 1,200 
gallons) of methanol would be consumed annually. 

EcoMat has indicated that they have a supplier that 
provides bulk purchases of methanol at a cost of $0.65 per 
gallon. Using that value, the annual cost of the methanol 
would be $780. The remainder of the methanol “solution” 
consists mostly of water. 

Nutrient supplements are also sometimes used. For the 
demonstration, a small amount of food grade phosphoric 
acid was added to the methanol solution to achieve a 
phosphorus concentration of about 0.75 ppm. The cost of 
the non-methanol portion of the solution is considered 
negligible and therefore is not included. 


23 



In some cases, additional substrates may be utilized. For 
example, during the demonstration, molasses was added 
to "kick start” the system. However, supplements such as 
molasses are not always needed and its cost is considered 
negligible and is not included here. 

3.5.6.2 Biocarrier Media 

The “EcoLink” biocarrier material is not replaced as long as 
it remains in suspension. Overloading does occur, 
therefore, after a significant period of time the EcoLink 
must be replaced before they sink and clog screens. 
EcoMat has indicated that a 100 gpm system requires 
abouttwo m 3 of EcoLink, which presently costs $6,000 per 
cubic meter. The developer has also estimated that 
approximately ten percent of the volume of EcoLink used 
in any sized system needs “refreshing" on an annual basis. 
Therefore, an annual cost of $1,200 for EcoLink biocarrier 
is assumed for this cost estimate. 

The bioballs used in the deoxygenating reactor tank are 
also a type of biocarrier. However, they can last indefinitely 
if periodically washed. For this reason, they are not 
considered as consumable. The labor cost of maintaining 
the bioballs is included in subsection 3.5.5.4 

3.5.6.3 Post-Treatment Consumables 

Post-treatment consumables would potentially include any 
chemical treatment added to the post-BDN effluent. Also 
included would be absorption and filtration media that 
would be spent over an indefinite time period and need 
replacement. Examples of such post-treatment media 
would be sand (used in sand filtration), spent activated 
carbon, spent filter cartridges, etc. 

It is assumed for this cost estimate that chlorination would 
likely be required when implementing the EcoMattreatment 
system for drinking water applications. EcoMat has 
indicated that they would use a 25% solution of liquid 
hypochlorite for full-scale chlorination post-treatment. For 
a 100 gpm system, they have estimated hypochlorite 
consumption at 2 gallons per day at a cost of 
approximately $6 per gallon. This daily rate would correlate 
to approximately 600 gallons of hypochlorite consumed 
annually at an estimated cost of $3,600. 

During the demonstration, EcoMat replaced the paper filter 
cartridges being used with cleanable metal cartridges. 
Activated carbon was used for one event only, and the 
sand filter was periodically flushed. For this cost estimate, 
it will be assumed the cleanable metal filter cartridges 
would also be used for a larger 100 gpm system. It will 
also be assumed that activated carbon will not be required 
and thatthe costof replacing sand filtration media would be 
negligible. Thus the cost of post-treatment consumables 
would consist solely of the hypochlorite cost, about $3,600 
annually. 


3.5.6.4 Equipment Rentals 

Equipment rentals would be an alternative to purchasing 
dedicated equipment for the full-scale treatment system. 
For example, a pressure washer could be rented for 
flushing out metal cartridge filters and reactor screens 
during periodic maintenance. A conservative cost estimate 
for renting a heavy duty pressure washer is $300/week. 
Assuming that pressure washing would be required 
quarterly, the annual rental charge would be approximately 
$1,200 per year. Since this annual cost exceeds 40% of 
the estimated purchase price, purchase of a pressure 
washer is the more economical choice. 

It should be noted that other equipment listed in the cost 
estimate as a capital expense may also be rented. During 
the demonstration, the SITE Program rented a colorimeter, 
pH/conductivity meter, a temperature/DO meter, a turbidity 
meter, and water level meter. However, as is the case with 
the pressure washer, the rental costs of these items for 
indefinite periods is not cost effective, especially when the 
periodic shipping charges are included. 

Since equipment that could be rented have been included 
as capital cost items, no rental costs are included in the 
cost estimates on Tables 3-1 and 3-2. 

The total estimated cost of consumables and supplies for 
the initial year of treatment is $5,580. The cost is estimated 
to increase proportionately with treatment duration. 

3.5.7 Utilities 

The main utility required for the EcoMat treatment system 
is electricity. Atthe Bendena site the electrical hookup and 
service were provided by the State of Kansas. The 
electricity provided the power needed to operate the 
system pumps and control panels, the submersible pump 
in the well, and outlets used for the building heater and the 
telephone/facsimile machine. The SITE Program recorded 
electric meter readings before, during, and at the 
conclusion of the demonstration. During the approximate 
I'A month period of time encompassed by the four 
sampling events, a total of approximately 26,400 kW-hr 
was used. Power usage rates varied in a range of 5.0-1 0.4 
kW. EcoMat has projected a 100 gpm system to utilize 
approximately 2.5 times the power of the pilot-scale 
system; which would correlate to a range of 12.5 - 26 kW 
of power. Conservatively using 20 kW as the power usage 
fora 100 gpm system, the number of kW-hrs used annually 
would be approximately 20 kW x 24 hr/day x 7 days/wk. x 
52 wk./yr or approximately 175,000 kW-hrs. Assuming a 
utility charge of $0.07/kWh, the cost of operation of the 100 
gpm treatment system for a year would thus be about 
$12,300. (Note: It is assumed that electric usage will 
continue when the system is off-line for testing and other 
maintenance activities.) It should be noted that electricity 
cost can vary greatly depending on geographical location. 


24 



There is also a need for a water line to operate a pressure 
washer for maintenance activities. However, the water 
usage is sporadic and is not expected to be substantial. 
Therefore, water usage is considered negligible for 
estimating utility costs. 

3.5.8 Effluent Treatment and Disposal 

For this technology successful treatment will mean that the 
effluent will become drinking water. Therefore, it is 
assumed that there will be no effluent treatment and 
disposal expense. It is assumed that the minimal amount 
of wastewater generated from periodic power washing of 
metal filter cartridges and reactor filter screens can be 
discharged either to a land septic system (as was the case 
at Bendena), or to a local POTW. 

3.5.9 Residuals Shipping and Disposal 

The only residuals generated during the demonstration 
were spent filter media (cartridges and carbon) and spent 
biocarrier media. Since levels of residual methanol are low 
in these wastes, most if not all of this material would be 
classified as non-hazardous and can be disposed of as 
such. 

It should be noted that if carbon is used to treat hazardous 
organic contaminants, any spent carbon could be classified 
as a hazardous waste, and thus require disposal as 
hazardous waste. 

For this cost estimate, it is assumed that no hazardous 
waste will be generated during treatment. Residuals 
would be discarded as non-hazardous solid waste. 
Disposal costs are, therefore, considered negligible for this 
cost estimate. 

3.5.10 Analytical Services 

Although nitrate and nitrite levels would be monitored 
continuously by an on-line nitrate analyzer, the state or 
local regulatory agency would still require independent 
analysis of effluent samples at some specified frequency. 
Based on discussions with the Public Works Supply 
Section of the KDHE, the required monitoring for a water 
treatment system such as EcoMat’s would include four 
specific drinking water criteria. These four criteria would 
include nitrate-N/nitrite-N (which is conducted as a single 
analysis), methanol, Fecal Coliform, and trihalomethanes 
(THMs). A likely monitoring schedule fora nitratetreatment 
system producing drinking water would include the 
following final effluent analyses at the indicated frequency: 

(1) Nitrate and nitrite quarterly; 

(2) Methanol quarterly; 

(3) Trihalomethanes (THM) quarterly; and 

(4) Fecal Coliform twice a month. 


The required monitoring would be conducted quarterly for 
the duration of the life of the treatment system, but would 
be at an increased level for the first 8 weeks of operation. 
For estimating the cost of the analytical services category, 
it is assumed that the treatment system effluent will be 
sampled three times a week for the first 8 weeks of 
operation (for a total of 24 samples) and then a total of 
three times for the remainder of the first year of operation 
in accordance with a quarterly sampling schedule. 
Therefore, a total of 27 effluent samples will be collected 
during the initial yearof system operation and four effluent 
samples will be collected for each successive year. 

The resulting first year total of 27 water samples, analyzed 
for nitrate-N/nitrite-N at an estimated cost of $15 per 
sample, methanolatan estimated costof$100 persample, 
Fecal Coliform at an estimated $15 persample, and THMs 
at an estimated $150 per sample would total to 
approximately $7,560. Assuming an increase of sample 
cost of 10 percent to cover QA samples, the total cost for 
the firstyear samples is estimated at $8,320. The total cost 
for each subsequent year of quarterly monitoring would be 
around $1,120. Again, assuming a 10 percent increase in 
costs to cover QA samples, the total cost for each 
subsequent year is estimated at about $1,230. 

It is anticipated that the VOC (methanol) and biological 
analyses would be conducted at separate off-site 
laboratories. The holding time requirements for nitrate- 
N/nitrite-N analyses and Fecal Coliform would necessitate 
near immediate shipments to those off-site laboratories, 
allowing for no holdovers. Therefore, separate shipments 
would be required for each. As a result there would be 54 
overnight shipments to the offsite laboratories during the 
first year of operation and eight shipments for each 
successive year. At an estimated $30/shipment for these 
small sample sets, the total cost of sample shipping 
services is estimated to be about $1,600 the first year and 
$240 each successive year. 

It should be noted that the stringency and frequency of 
monitoring required may have a significant impact on this 
cost category. 

3.5.11 Maintenance and Modifications 

Once the treatment system is in full operation (following the 
shakedown and recycling phase) monitoring and periodic 
maintenance are necessary to maintain the required level 
of the treatment. 

For this cost estimate it will be assumed that most of the 
system operation will be monitored remotely from off-site. 

Based on the observations made during the SITE 
demonstration, the mostly likely maintenance problems 
would involve system disruptions due to clogged filters or 
screens. The cost associated with these problems is 
mostly labor and did not involve the purchase of 


25 



replacement parts during the demonstration (see 
subsection 3.5.5.4). It is assumed that system components 
having high replacement costs (such as pumps) will 
operate for the full duration of treatment if maintained 
properly. Components that were replaced during the 
demonstration included those having a relatively low cost 
(such as malfunctioning switches and level sensors). 

EcoMat has estimated non-labor cost of maintenance to 
be approximately 1 percentof the treatment system capital 
cost annually, which is roughly $2,600. 

3.5.12 Demobilization 

In general, EcoMat believes that much of the equipment 


comprising the biodenitrification treatment system (if not all) 
will be reusable. The end use of the equipment would be 
determined on a case-by-case basis. Demobilization 
would be performed at the conclusion of the entire project, 
which is dependent on the total treatment time. It is 
possible that treatment would be indefinite or would be of 
long enough duration that the equipment components 
would be fully depreciated, thus essentially making the cost 
of disassembly and shipment to a second location 
prohibitive. In eithercase, this cost estimate assumes that 
the responsible party owns the system through their capital 
cost investment. Therefore, demobilization is not an issue, 
and all equipment has zero salvage value. 


26 



Section 4.0 

Demonstration Results 


4.1 Introduction 

4.1.1 Project Background 

EcoMat’s BDN Process was evaluated under the SITE 
Program at the former PWS Well #1 in Bendena, Kansas. 
The primary contaminant in the well water is nitrate-N, 
which historically has been measured at concentrations 
ranging from approximately 20 to 130 ppm, wellabovethe 
regulatory limitof 10 mg/I. VOCs, notably CCI 4 , have been 
a secondary problem. The overall goal of EcoMat was to 
demonstrate the ability oftheir process to reduce the levels 
of nitrate-N in the groundwater and restore the public water 
supply well as a drinking water source. 

The SITE demonstration occurred between May and 
December of 1999 and was conducted in cooperation with 
the KDHE. The study consisted of four separate sampling 
events interspersed over a I'A month time period. During 
these four events EcoMat operated its system at flows 
between three and eight gpm. During this same time 
period well water nitrate-N levels varied from greater than 
70 mg/I to approximately 30 mg/I. 

During the four sampling events, the SITE Program 
collected water from four specific sample taps located 
along EcoMat’s process. Sampling rounds were 
scheduled at pre-specified intervals, and consisted of 
collecting the water samples from thefoursample locations 
at the approximate same time. By following this procedure 
the data collected simultaneously from the four sample 
locations could be compared to one another. A total of 119 
samples from each of the four sampling locations were 
collected for the four field events (28 for Event 1; 31 for 
Event 2; and 30 each for Events 3 and 4). 

The four sample points, as shown on Figure 4-1, are: 

1. An untreated (“Inlet Water”) sample point located 
between PWS Well # 1 and the Deoxygenating 
Tank (SI); 

2. A “Partial BDN Treatment”sample point located 
between the Deoxygenating Tank and EcoMat 


Reactor (S2); 

3. A “Post BDN” sample point located between the 
EcoMat Reactor and post-treatment system (S3); 

4. A “Final Effluent” sample point located 
downstream of the post-treatment system (S4). 

4.1.2 Project Objectives 

Specific objectives for this SITE demonstration were 
developed and defined prior to the initiation of field work. 
These objectives were subdivided into two categories; 
primary and secondary. Primary objectives are those goals 
of the project that need to be achieved to adequately 
compare demonstration results to the claims made by the 
developer. The field measurements required for achieving 
primary objectives are referred to as critical 
measurements. Critical measurements were formally 
evaluated against regulatory limits using statistical 
hypothesis tests (which are detailed in the TER). 

Secondary objectives are other goals of the project 
developed for acquiring additional information of interest 
about the technology, but are not directly related to 
validating developer claims. The field and laboratory 
measurements required forachieving secondary objectives 
are considered to be noncritical. Therefore, the analysis of 
secondary objectives was more qualitative in nature and 
involved observations made by summarizing data in tables 
and graphs. 

Table 4-1 presents the one primary and seven secondary 
objectives of the demonstration, and summarizes the 
method(s) by which each was evaluated. Except for the 
cost estimate (Objective 8), which is discussed in Section 
3, each of these objectives is addressed in this section. 

4.2 Detailed Process Description 

A process flow diagram of the EcoMat treatment systems 
used for the demonstration is presented in Figure 4-1. As 
illustrated, there are two major components comprising the 


27 









Figure 4-1. Flow Diagram Showing EcoMat’s Treatment System and Sample Collection Points 


process: a BDN system and a post-treatment system. The 
BDN system is a type of fixed film bioremediation in which 
specific biocarriers and bacteria are used to convert 
nitrates in the groundwater to nitrogen, thus reducing 
nitrate-N concentrations to acceptable levels. The post¬ 
treatment system is designed to either destroy or remove 
any intermediate compounds potentially generated during 
the biological breakdown of nitrate, and to remove small 
amounts of bacteria and suspended solids that are not 
attached to the biocarrier. The post-treatment system 
shown in Figure 4-1 is a compilation of the different 
combinations that were used during the demonstration. As 
illustrated, the post-treatment system can incorporate 
traditional methods for treating other contaminants (e.g., 
VOCs) that may be present in the influent. Both the BDN 
and post-treatment systems are discussed in greater detail 
in the following subsections. 

4.2.1 BDN System 

EcoMat’s BDN system is designed to allow for rapid and 
compact treatment of nitrate with minimal byproducts. 
Unique to EcoMat’s process is a patented mixed reactor 
that is designed to retain the biocarrier within the system, 
thus minimizing solids carryover. A detailed schematic of 


the EcoMat denitrification reactor flow pattern is shown in 

Figure 4-2. 

A 50 percent aqueous methanol (MeOFI) solution is added 
to the system to provide an oxygen scavenger for BDN and 
a source of carbon for cell growth. The resulting oxygen- 
deficient environment encourages the bacteria to consume 
nitrate. Methanol is also important to assure that 
conversion of nitrate proceeds to the production of nitrogen 
gas rather than to the intermediate nitrite, which is 
considered to be more toxic. 

The mechanism for anoxic biodegradation of nitrate 
consists of an initial reaction for removal of excess oxygen 
followed by two sequential denitrification reactions. This 
mechanism can be expressed as three separate equations 
as follows: 

Oxygen Removal 

CH 3 0H + 1.50 2 -> C0 2 + 2H 2 0 (1) 

Denitrification Step 1: 

CH 3 0H + 3N0 3 --> 3N0 2 - + C0 2 + 2H 2 0 (2) 

Denitrification Step 2: 

CH3OH + 2N0 2 --> N 2 + C0 2 + 20H' + H 2 0 (3) 


28 


































































Table 4-1. Demonstration Objectives. 


Objective 

Description 

Method of Evaluation 

Primary Objective 


Objective 1 

Evaluate the performance of the EcoMat BDN and post-treatment 
process components, separately; with respect to the following 
performance estimates: 

I. With incoming groundwaterhaving nitrate-N concentrations of 20 
mg/I or greater, and operating at a flow through rate of 3-15 gpm, 
the BDN unit would reduce the combined nitrate-N and nitrite-N 
(total-N) concentration from PWS Well #1 groundwater to at or 
below a total-N concentration of 10 mg/I. 

II. The post treatment unit(s) will produce treated groundwater that 
will meet applicable drinking water standards with respect to 
nitrate-N, nitrite-N, and the combined nitrate-N plus nitrite-N. 

III. Coupled with planned or alternative post-treatment, the product 
water will consistently meet drinking water requirements, except 
for residual chlorine. Specifically it will not contain turbidity of 
greater than 1 NTU, detectable levels of methanol (1 mg/I), or 
increased levels of biological material or suspended solids, and 
will have a pH in the acceptable 6.5-8.5 range. 

Collect post BDN effluent and final effluent samples from 
two critical outfalls, interspersed over a period of four 
events. Determine nitrate-N and nitrite-N concentrations 
in those effluent samples via EPA Standard Method 
300.0. 

Note: For the purpose of performance evaluation, effluent 
nitrate-N (and similarly the total-N) concentrations of 

10.49 mg/I were to be rounded down to 10 mg/I and 
therefore considered as meeting the MCL and 10.50 mg/I 
were to be rounded up to 11 and therefore considered as 
failing the MCL. Similarly, nitrate-N concentrations of 

1.49 mg/I were to be rounded down to 1 mg/I and 
therefore considered as meeting the MCL and 1.50 mg/I 
were to be rounded up to 2 mg/I and therefore considered 
as failing the MCL. These decisions were based on 
discussions with the KDHE and reflect its current 
practices.<10.5 mg/I when rounded to three significant 
digits). The detailed statistical equations and data 
analysis procedures used for evaluating the 
demonstration data are included in the TER. 

Secondary Objectives 


Objective 2 

Evaluate the performance of EcoMat’s combined BDN and post¬ 
treatment system components with respect to influent nitrate-N 
concentration and with respect to time and/or water flow. 

Plot the Objective 1 data versus 1) the influent 
concentration from PWS Well # 1 and 2) the average flow 
rate for each event. 

Objective 3 

Demonstrate that at least 90% of the final effluent samples 
(downstream of post-treatment) analyzed during the demonstration 
period for methanol, turbidity, and biological materials meet 
drinking water requirements or at least do not provide cause for 
concern where numerical values cannot be used for guidance. 

Collect samples for methanol, total heterotrophs, fecal 
coliform, and facultative anaerobes analyses at a 
frequency of one per day from all four outfalls and 
conduct daily turbidity measurements collected at inlet 
water, post BDN, and final effluent sample streams. 

Objective 4 

Evaluate the percent mass removal of nitrate-N during each 
sampling period over the course of the demonstration. 

Calculate the total inlet and final effluent nitrate-N masses 
in grams; determine mass removed as a total and 
percentage. 

Objective 5 

Evaluate the effectiveness of the post-treatment system in 
removing suspended solids, biologically active materials, methanol, 
and VOCs of interest (e.g., carbon tetrachloride, benzene and 
tetrachloroethylene). 

Collect daily samples at all four outfalls for TSS analysis. 
Collect inlet water, post-BDN, and final effluent samples 
for VOC analysis at a frequency of three per event, and 
conduct PLFA analysis at least once at all four outfalls. 

Objective 6 

Evaluate the necessity of the post-treatment system for 
contributing to nitrate and nitrite mass removal. 

Compare nitrate-N and nitrite-N mass results before and 
after post-treatment. 

Objective 7 

Evaluate the effectiveness of each post-treatment system used 
during the demonstration for removing suspended solids, bacterial 
material, methanol and other VOCs. 

Compare the data acquired for Objective 3 on an inter¬ 
event basis. 

Objective 8 

Collect and compile information and data pertaining to the cost of 
implementing the EcoMat BDN Process and necessary post¬ 
treatment for the removal of excessive levels of nitrate in drinking 
water supplies. 

Acquire cost estimates from past SITE experience and 
from developer. Cost treatment for a full-scale system 
similar in design to the pilot unit used at Bendena. Break 
down estimates into 12 cost categories that reflect typical 
cleanup activities at Superfund sites. (See Section 3) 


29 
















CIRC 

PUMP 


Figure 4-2. Detailed Schematic of the EcoMat Denitrification Reactor. 


30 


















































Overall Denitrification Reaction: 

5CH 3 OH + 6N0 3 ' > 3N 2 + 5C0 2 + 60H' + 7H 2 0 (4) 

Note: The subsequent discussion refers to nitrate-N and 
nitrite-N values, in which each mg/I of nitrate-N is 
equivalent to 4.4 mg/I of nitrate and each mg/I of nitrite-N 
is equivalent to 3.2 mg/I of nitrite. 

In the first step, aerobic/facultative bacteria consume 
oxygen in the process of metabolizing methanol forenergy 
and biomass production. For the first denitrification step 
(Equation 2) to occur, it is essential that the dissolved 
oxygen (DO) concentration be less than 1 mg/I. Under 
these anoxic conditions, the bacteria are forced to 
substitute the nitrate as the electron acceptor and the 
nitrate is reduced to nitrite. In the third equation, the nitrite 
is further reduced to nitrogen gas. Nitrite production is an 
intermediate step and there is no a priori reason to assume 
that the second reaction (Equation 3) is at least as fast as 
and/or favored over the first reaction (Equation 2) in the 
presence of a specific bacterial population. Consequently, 
any evaluation scheme must establish that there is no 
buildup of nitrite, particularly since the nitrite-N maximum 
contaminant level (MCL) is only 1 mg/I, one tenth that of 
nitrate-N. High concentrations of nitrate and high 
nitrate/methanol ratios tend to increase the concentration 
of residual nitrite-N. 

BDN is conducted in two reactors, identified as R1 and R2 
on Figure 4-1. The majority of the oxygen removal step 
(Equation 1) is conducted within R1, which EcoMat refers 
to as the “Deoxygenating Tank”. Inside this tank are 
bioballs (a standard type of biocarrier) which have been 
loaded with de-nitrifying bacteria purchased from a 
commercial vendor. These aerobic bacteria initially reduce 
DO levels of the contaminated influent. A 50 percent 
aqueous MeOH solution is metered to the tank to 
encourage the bacteria to begin consuming nitrate in the 
resulting oxygen deficient water. 

The deoxygenated water is pumped from the bottom of R1 
to the bottom of R2, which is referred to by the developer 
as the “EcoMat Reactor”. R2 is packed with a synthetic 
polyurethane biocarrier called “EcoLink”, which serves as 
the biocarrier for a colony of additional bacteria that are 
also cultured for degrading nitrate. The EcoLink media are 
1-cm 3 cubes of sponge-like material that provide a large 
surface area for growing and sustaining an active bacteria 
colony. The cubes have contiguous holes so that bacteria 
can populate them and nitrogen gas can exit. A special 
additive to the polyurethane makes the surface more 
hospitable to the bacteria. 

Specially designed mixing apparatus within R2 directs the 
inflowing water into a circular motion, which keeps the 
suspended media circulatingand enablesthe contaminated 
waterto have intimate contact with the bacteria. Perforated 
plates at the bottom and top of R2 retain the EcoLink 


biocarrier within the reactor, while permitting passage of 
the water. Before the production of nitrogen gas starts the 
specific gravity of EcoLink is slightly greater than that of 
water. Within R2, the majority of denitrification (Equations 
2 and 3) is conducted by the established anaerobic 
bacteria colonies that are continually fed methanol as a 
carbon source. After a sufficient retention time the 
denitrified water drains by gravity to an overflow tank, 
which allows for a continuous and smooth transfer to the 
post-treatment system. 

4.2.2 Post-Treatment System 

The post-treatment system can be comprised of two 
primary treatment components; an oxidation component 
and a filtration component. The oxidation component is 
intended to oxidize residual nitrite back to nitrate, oxidize 
any residual methanol, and destroy bacterial matterexiting 
the EcoMat Reactor (R2). The oxidation component may 
consist of chlorination, ozonation, or UV treatment; or a 
combination of the three. During the demonstration, 
chlorination was used fortwo events, UV was used forone 
event, and an ozone/UV combination was used for one 
event. 

The filtration component usually consists of a clarifying 
tank and one or more filters designed to remove 
suspended solids generated from the BDN process. 
During the demonstration, a variety of filter combinations 
were used, including a sand filter, and a series of variable¬ 
sized cartridge filters. The cartridge filters that were used 
included "rough filters" (20pm), "high efficiency filters" 
(5pm), and “polishing filters” (1 pm). Carbon cartridge filters 
and an air stripper were used during Events 3 and 4, 
respectively, to remove small amounts of CCI 4 . 

4.3 Field Activities 

4.3.1 Pre-Demonstration Activities 

To confirm contaminant concentrations for the 
demonstration and assist in sizing the system, pre¬ 
demonstration samples were taken from PWS Well # 1 
overa nine-day period (September 22-30,1998). Since the 
pilot-scale system was expected to be operated within the 
3-15 gpm range, itwas decided to pump groundwaterfrom 
the well at 10 gpm during the nine-day period. To provide 
an indication of the variation in nitrate-N concentrations, 
one sample was collected every two hours over a four-hour 
period, at the same times each day. It was also realized 
during the pre-demonstration activities that pumping at a 
rate of 20 gpm over a five-day period lowered the water 
level in the well by about 10 feet, over 20 percent of the 
water column. When the pumping rate was reduced to 
about 10 gpm, there was little drawdown in the well. 


31 



4.3.2 Sample Collection and Analysis 

The sampling strategy for evaluating the effectiveness of 
EcoMat’s BDN Process was developed around comparing 
the post BDN and final effluent (after post-treatment) data 
to applicable regulatory limits. This comparison addresses 
the project Primary Objective as presented in Table 4-1. 

As was explained previously, there were four separate 
treatment events during the demonstration. These events 
were partially determined based on anticipated changes to 
the post-treatment system. The events were spread out 
over several months to allow for evaluating the EcoMat 
technology over a longer time duration. 

The goal of the sampling strategy was to collect sufficient 
samples at each critical outfall during each event so that 
statistical hypothesis tests could be conducted with an a 
error rate = 0.10 and a P error rate = 0.10. (The method for 
calculating the number of samples is presented in more 
detail in the TER). Using 5.5 mg/I as an estimate of the 
population variance in the final effluent nitrate-N + nitrite-N 
(total-N) measures, the number of sampling rounds 
required per event was found to be 29. 

The SITE Program conducted on average - 30 sample 
sampling rounds for each event. Since the samples were 
collected at each of the four locations at the same time, the 
resulting sample sets were comparable for evaluating the 
EcoMat process atdifferent points of the process; either on 
a “per sample round" or “per event” basis. In order to 
achieve some level of “flushing” between sampling rounds, 
the daily sampling frequency during each event was 
dependent on the water flow rate through the system. 
Because the flow rate was varied for each event, the 
number of daily sampling rounds for collecting sample sets 
varied from 3 to 5 per day. 

The effectiveness of the post-treatment systems for all 
events was evaluated by collecting samples immediately 
downstream of the BDN system (“post BDN”), and 
immediately downstream of the developer-selected post- 
treatmentcomponents (“final effluent"); then comparing the 
sample results from the two outfalls with respect to a 
variety of microbial and water quality parameters. These 
parameters included, but were not limited to, residual 
methanol, total suspended solids (TSS), turbidity, total 
culturable heterotrophs (TCH), Fecal Coliform (FC), and 
facultative anaerobes (FA). Phospholipid fatty acids (PLFA) 
were analyzed for on a very limited basis. Since these 
limited PLFA results do not impact any developer claims, 
those results are presented in the TER only. 

Table 4-2 presents a summary of the laboratory analyses 
conducted on samples collected from each of the four 
sampling points monitoring the EcoMattreatment process, 
and for the methanol feed (the main additive for the 
process). All samples collected were grab samples. 


4.3.3 Process Monitoring 

Process monitoring was conducted on a routine daily basis 
during all four sampling events. Table 4-3 presents the 
type of process monitoring conducted during the 
demonstration, the frequency and location of that 
monitoring, and the instrumentation used. Details are 
provided in the following subsections. 

4.3.3.1 Nitrate-N and Nitrite-N Colorimeter Testing 

Although daily samples were being collected during each 
event for laboratory nitrate-N and nitrite-N analyses, 
colorimeter testing was also conducted daily to 
approximate real time values for those critical parameters. 
These measurements aided the developer in making 
adjustments to its system and aided the analytical 
laboratory in determining calibration ranges. An on-line 
nitrate monitor was also installed to provide a continuous 
record of nitrate entering and leaving the treatment system, 
but the unit could not be operated routinely and no useful 
records were obtained. 

4.3.3.2 Process Flow Rate 

Flow measurements were taken from a totalizer meter to 
ensure that sampling rounds were being conducted at the 
properly-spaced time intervals (i.e., the treated water 
correlated to the previous sampling round had exited the 
entire treatmentsystem).The flow measurements were also 
used for later calculation of flow rates that could be 
correlated to analytical results for each sampling round 
conducted. A calibration check of the Neptune totalizer 
gauge was conducted for each event to assure accuracy 
of the meter. 

4.3.3.3 General Water Quality Parameters 

Daily measurements of general water quality parameters 
were taken at all four outfalls to monitor parameters that 
either could directly affect biological activity (e.g., 
temperature and DO) or were to be used to evaluate 
system performance with respect to secondary objectives 
(e.g., pH and turbidity). All water quality parameters were 
measured with field instrumentation thatwas calibrated per 
manufacturer instructions prior to taking the 
measurements. 

4.3.4 Process Residuals 

During the demonstration the developer was responsible 
for disposing of process residuals. These mostly included 
spent cartridge filters, spent biocarrier, and spent carbon. 

Due to the fact that nitrate and nitrite are non-hazardous 
with respect to RCRA regulations, and that VOC 
concentrations were negligible, all residuals from the 
process were considered non-hazardous. Thus the spent 


32 



Table 4-2. Summary of Laboratory Analyses Conducted for the Demonstration. 


PARAMETER 

Test 

Method 

SAMPLE LOCATION POINTS 

METHANOL 

FEED 

INLET 

WATER 

PARTIAL 

BDN 

POST 

BDN 

FINAL 

EFFLUENT 

Chemical Analyses 

Nitrate-N 

EPA 300.0 

Each Round 1 

Each Round 1 

Each Round 1 

Each Round 1 

— 

Nitrite-N 

EPA 300.0 

Each Round' 

Each Round 1 

Each Round 1 

Each Round 1 

_ 

TSS 

EPA 160.2 

1 per day 

1 per day 

1 per day 

1 per day 

__ 

Methanol 

SW 8015 

1 per day 

1 per day 

1 per day 

1 per day 

... 

VOCs 

SW 8260 

3 per Event 

_ 

3 per Event 

3 per Event 

2 per Demo. 

Total Metals 

SW 3010/6020 

3 per Event 

... 

3 per Event 

3 per Event 

_ 

Sulfate 

EPA 300.0 

3 per Event 

_ 

3 per Event 

3 per Event 

_ 

Alkalinity 

EPA 310.1 

3 per Event 

... 

3 per Event 

3 per Event 

— 

Total Solids 

EPA 160.3 

3 per Event 

— 

3 per Event 

3 per Event 

... 

Phosphate 

EPA 300.0 

3 per Event 

— 

3 per Event 

3 per Event 

— 

Ammonia 

EPA 350.2 

3 per Event 

... 

3 per Event 

3 per Event 

— 

Total Organic Carbon 

SW 9060 

3 per Event 

— 

3 per Event 

3 per Event 

— 

Microbial Analyses 

Total Heterotrophs 

SOP 

1 per day 

1 per day 

1 per day 

1 per day 

— 

Fecal Coliform 

SOP 

1 per day 

1 per day 

1 per day 

1 per day 

— 

Facultative Anaerobes 

SM 9215 M 

1 per day 

1 per day 

1 per day 

1 per day 

— 

PLFA 

SOP GCLIP 

1 for Event 1 

1 for Event 1; 

1 for Event 4 

1 for Event 1; 

1 for Event 4 

1 for Event 1 

... 


1 Refers to a round of samples collected from the process sample location points (Figure 4-1) at approximately the same time. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-3. Summary of Field Measurements Conducted for the Demonstration. 1 




SAMPLE LOCATION POINTS 

PARAMETER 

INSTRUMENTATION 

INLET 

PARTIAL 

POST 

FINAL 

WATER 

BDN 

BDN 

EFFLUENT 

Nitrate-N 

Hach DR-890 Colorimeter 

1 per day 

— 

1 per day 

— 

Nitrite-N 

Hach DR-890 Colorimeter 

— 

— 

1 per day 

— 

Flow Rate 

Neptune Totalizer 

Each Round 

Each Round 

Each Round 

Each Round 

pH 

YSI Mod. 63 pH/Cond. meter 

1 per day 

1 per day 

1 per day 

1 per day 

Conductivity 

YSI Mod. 63 pH/Cond. meter 

1 per day 

1 per day 

1 per day 

1 per day 

Dissolved Oxygen 

YSI M95 DO meter 

1 per day 

1 per day 

1 per day 

1 per day 

Temperature 

YSI M95 DO meter 

1 per day 

1 per day 

1 per day 

1 per day 

Turbidity 

LaMotte 2020 Turbidmeter 

1 per day 

1 per day 

1 per day 

1 per day 


1 In addition, daily water levels of PWS Well #1 were recorded and electric usage was periodically recorded during each Event. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


33 
























































filter cartridges, carbon, biocarrier, etc. were simply 
collected in a trash container and disposed of in a solid 
waste dumpster. 

The final effluent was deemed non-hazardous by the 
KDHE, who arranged fora permit to discharge the treated 
water to a septic system installed in an agricultural field 
downgradient of the EcoMat treatment shed and PWS 
Well #1. 

4.4 Performance and Data Evaluation 

This subsection presents in summary form the 
performance data obtained during the EcoMat SITE 
Demonstration conducted from May to December, 1999. 
The data are presented in two ways. Subsections 4.4.1 
through 4.4.4 evaluates each sampling event (i.e., Events 
1 through 4, respectively), independently, with respect to 
the objectives listed in Table 4-1. Subsection 4.4.5, on the 
other hand, compares a II four events. The latter inter-event 
comparison may provide the reader with a better 
understanding of the overall demonstration. Subsection 
4.4.6 summarizes data quality assurance aspects of the 
demonstration. 

Since the post-treatment system was varied for each event, 
the data from the four events were initially analyzed 
separately. Then a comparison between events was 
performed. The level of significance (LOS) or a error rate 
was set to 0.10 for the various statistical tests performed. 
These tests included the Shapiro-Wilk tests of Normality 
followed by either the Wilcoxon Signed Rank test or the 
Student’s t-test. The Wilcoxon Signed Rank (WSR) test is 
a non-parametric, one-sample test, used to test the median 
against a fixed threshold such as a regulatory limit. The 
one-sample Student’s t-test is a parametric testwhich tests 
the mean against a fixed threshold. 

Within each of these subsections, the following discussions 
are presented in sequence: 

• a summary of the effectiveness of the EcoMat 
BDN and post-treatment systems at the various 
sampling points. 

• results of the statistical analysis that were 
conducted to compare post BDN and final effluent 
data to the appropriate regulatory limits. 

• an evaluation of the BDN system. 

• post-treatment system performance. 

• a summary on the mass removal of nitrate. 

• a discussion of the possible relationship between 
system performance and flow rate. 

To evaluate the post BDN and final effluent data against 
regulatory limits, the following analytical strategy was used. 


For each separate event, an Exploratory Data Analysis 
(EDA) was conducted for the post BDN combined nitrate- 
N/nitrite-N (total-N), the final effluent nitrate-N, the final 
effluent nitrite-N, and the final effluent total-N. The EDA 
consisted of graphing the data in several formats and 
calculating summary statistics (i.e., mean, median, and 
standard deviation). These graphs and summary statistics 
were used to make preliminary assumptions about the 
shape of the distributions of the variables. This information 
was needed in order to identify the appropriate statistical 
hypothesis tests for the data. 

After reviewing the graphs and summary statistics, 
Shapiro-Wilk tests of Normality were performed. Based on 
the results of these tests, either the WSR test or the 
Student’s t-test was chosen as the appropriate hypothesis 
test (i.e., the non-parametric WSR test was chosen when 
the data did not fit either a normal or log-normal distribution 
and the Student’s t-test was chosen when the data 
resembled a normal distribution). When the WSR test was 
used the mean of the variable was evaluated against the 
appropriate demonstration criterion. When the Student’s t- 
test was used the median of the variable was evaluated 
against the appropriate demonstration criterion. 

The demonstration criterion was the regulatory limit when 
rounded to a whole number. The post BDN total-N was 
tested against the demonstration criterion of < 10.5 mg/I 
(i.e., regulatory limit = 10 mg/I), using an a error rate of 
0.10. The final effluent had to meet a combined criteria 
where the mean or median nitrate-N was < 10.5 mg/I (i.e., 
regulatory limit = 10 mg/I), the mean or median nitrite-N 
was < 1.5 mg/I (i.e., regulatory limit = 1 mg/I), and the mean 
or median total-N was below 10.5 mg/I (i.e., regulatory limit 
= 10 mg/I). All three of these criteria had to be met in 
order for the technology to be considered successful. 
Therefore, a family-wise a error rate was set at 0.10 for 
these three tests. 

4.4.1 Event 1 

4.4.1.1 Summary 

Event 1 was an 11-day sampling episode conducted May 
5-15, 1999. During Event 1 a total of 28 sampling rounds 
were conducted and -42,000 gallons of nitrate- 
contaminated well water passed through EcoMat’s 
treatment system at an average flow rate of 3 gpm. Based 
on average flow rate and an estimated retention capacity 
of 1,300 gallons for the reactor tanks, the sample rounds 
were conducted three times per day and approximately 
seven hours apart. 

Figure 4-3 separately illustrates the effectiveness of the 
EcoMat BDN and post-treatment systems evaluated during 
Event 1, on an averaged basis (Note: the term average is 
also referred to as the mean in subsequent discussions). 
The top illustration shows BDN effectiveness for reducing 
nitrate in the well water as a step-by-step process. As 


34 




80 


60 



20 


0 


INLET 


WATER 


(from PWS 
Well #1) 



PARTIAL BDN 
TREATMENT 



/ \ 

R2 


EcoMat 

Reactor 



Event 1 

Flow @ 3 gpm 
Legend 

46 = Total-N concentration (mg/I) 

(43/3) = Nitrate-N / Nitrite-N concentration (mg/I) 

BDN = Biodenitrification 

ND = Not detected > detection limits 


POST BDN 

TREATMENT 

(R2 Effluent) 


1.9 

(0.9/1) 


FINAL 

EFFLUENT 


{> 


POST 
TREATMENT 
(see below) 


i> (1.7/0.4) 


Event 1 Post-Treatment Effectiveness 


Post BDN 


Final Effluent 


MeOH = 5.8 
TSS = 12 
Turbidity = 2.8 
TCH = 2.4x10* 
FC = 0 

FA = 3.6x10* 





MeOH = 15 
TSS = 10 
Turbidity = 4.4 
TCH = 2.7 x 10* 
FC = 0 

FA = 3.4 x10 s 


Figure 4-3. Event 1 - Treatment Effectiveness for Averaged Test Results. 


illustrated, the nitrate-N concentration in PWS Well#1 was 
in excess of 70 mg/I during the first event in May of 1999. 
This high level of nitrate-N was reduced by about 38% 
during the partial BDN treatment process that occurred in 
the first reactor (R1). A small amount of nitrite, 3 mg/I, 
remained from the nitrate-nitrite conversion. Subsequent 
treatment in the EcoMat Reactor (R2) further reduced the 
mean nitrate-N concentration from 43 mg/I to 0.9 mg/I and 
reduced the mean nitrite-N level from 3 mg/I to 1 mg/I. 


Thus, a mean total-N concentration of 1.9 mg/I was 
attained by BDN treatment for Event 1 effluent samples. 

Post-BDN and final effluent samples had essentially the 
same total-N concentration. Mean total-N concentrations 
for post-BDN and final effluent samples were 1.9 mg/I and 
2.1 mg/I, respectively. However, the mean nitrate-N 
concentration increased approximately twofold and the 
mean nitrite-N concentration decreased by more than half. 


35 



























At these low levels, variability in laboratory analyses may 
be an explanation, although continued biological activity 
between the BDN and post-treatment processes may also 
be a contributing factor. Alternatively, the post-treatment 
chlorination may simply be re-oxidizing nitrite back to 
nitrate. 

As shown in the bottom illustration of Figure 4-3, the only 
post-treatment conducted during Event 1 was chlorination. 
The addition of chlorine had little effect on mean 
concentrations of methanol. The mean methanol and 
turbidity levels actually increased following post-treatment, 
while mean TSS concentrations remained essentially the 
same. As a disinfecting agent, the chlorination may have 
had a modest impact on residual biological material. 
Although TCH remained essentially the same, FA counts 
were measured on average to decrease by one order of 
magnitude. There was no growth for FC, thus there was 
no measured post-treatment effect for that parameter. 

4.4.1.2 Event 1 Statistical Analysis 

The summary statistics for the critical measurements are 
presented in Table 4-4. The nitrate-N, the nitrite-N, and 
the total-N results forthe four sampling locations, for all 28 
tests comprising Event 1 are shown in Table 4-5. The 
average (i.e., mean) values from these data were used in 
generating Figure 4-3. These data were also used to 
evaluate the Primary Objective (Objective 1). 


Table 4-4. Event 1 - Summary Statistics. 

Critical 

Measurement 

Mean 

(mg/l) 

Median 

(mg/l) 

Standard 
Deviation (mg/l) 

Post BDN Total-N 

1.917 

1.270 

1.474 

Final Effluent 

Nitrate-N 

1.654 

1.600 

1.509 

Final Effluent 

Nitrite-N 

0.410 

0.113 

0.424 

Final Effluent 1 2.064 

Total-N 

1.676 

1.445 


The EDA showed that the data for all four measurements 
from Event 1 more closely resembled a lognormal than a 
normal distribution. However, normality and lognormality 
were rejected for all measurements, using an a error rate 
of 0.10. (In other words, at the selected or error rate of 
0.10, these data did not fit either a normal or a lognormal 
distribution). Therefore, the non-parametric WSR was 
chosen for analyzing the data and the median was used as 
the appropriate measure of central tendency. 

Statistical hypothesis tests thatwere conducted yielded the 
following results: 


• Part I: Post BDN median total-N of 1.27 mg/I was 
significantly below the criterion of 10.5 mg/I. 

• Part II: Final Effluent met the combined criterion. 
The median total-N of 1.68 mg/I was significantly 
below the criterion of 10.5 mg/I. 

Based on the results of these 2 hypothesis tests, Event 1 
was shown to be successful in reducing levels of nitrite-N 
and nitrate-N to below regulatory limits, with a LOS of 0.10. 
A more detailed explanation of these results is presented 
in the TER. 

4.4.1.3 General Evaluation of BDN System 

Table 4-6 presents a summary of all performance criteria 
results for Event 1. This includes the post-BDN and final 
effluent nitrate-N, nitrite-N, and total-N data for each of the 
28 Event 1 tests. Also included are the additional analytical 
and field measurement data for specific outfalls that were 
used for evaluating other performance criteria. As shown, 
the objectives regarding reductions in nitrate-N, nitrite-N, 
and total-N in final effluent were attained for all 28 sample 
sets. However, other performance criteria results indicated 
the need for more substantial post-treatment, especially for 
treating residual methanol and removing microbial matter. 

The daily DO measurements in Table 4-7 are key 
indicators for evaluating the effectiveness of the 
deoxygenating step required for triggering the anaerobic 
BDN process. The data show that the deoxygenating 
process was effective in reducing an average inlet water 
DO of 10 mg/I to approximately 1 mg/I in partially treated 
water exiting the Deoxygenating Tank. 

4.4.1.4 General Evaluation of Post-Treatment System 

Presented in this subsection are the field and laboratory 
measurement data that were used primarily for evaluating 
the post-treatment component of EcoMat’s process during 
Event 1 (Objective 5). Parameters included pH, turbidity, 
TSS, microbial analyses, methanol, and “supplemental 
analyses” which included a variety of parameters sampled 
and analyzed on a limited basis. 

The daily pH measurements in Table 4-8 show a slight 
increase in pH to occur following BDN treatment. The post¬ 
treatment chlorination thatfollowed BDN may have caused 
a very slight upward shift in the pH range. This negligible 
effect was expected since chlorination is not a pH-altering 
post-treatment (i.e., as opposed to ozone). 

The daily turbidity measurements in Table 4-9 are 
considered a gross indicator measurement for evaluating 
the production of solids in the BDN system and a measure 
of the effectiveness of the post-treatment system in 
removing solids carryover. Since there is a secondary 
criteria drinking water standard associated with turbidity, 
each day of sampling was evaluated independently to 


36 

















Table 4-5. Event 1 - Nitrate-N and Nitrite-N Results (mg/I). 


Sample 
Round ’ 

Nitrate-N 

Inlet Water 

Nitrite-N 

Total-N 1 2 

Nitrate-N 

Partial BDN 

Nitrite-N 

Total-N 2 

Nitrate-N 

Post BDN 

Nitrite-N 

Total-N 2 

Nitrate-N 

Final Effluent 

Nitrite-N 

Total-N 2 

1 

77.9 

<0.076 

77.9 

34.9 

4.8 

39.7 

1.2 

1.3 

2.5 

2.5 

< 0.15 

2.65 

2 

77.7 

<0.076 

77.7 

47.9 

2.9 

50.8 

1.2 

0.67 

1.87 

2.2 

< 0.15 

2.35 

3 

79.2 

<0.076 

79.2 

50.0 

2.6 

52.6 

4.7 

1.1 

5.8 

5.3 

0.26 

5.56 

4 

79.3 

<0.076 

79.3 

47.7 

3.3 

51.0 

3.7 

1.4 

5.1 

3.8 

1.3 

5.10 

5 

79.5 

<0.076 

79.5 

50.5 

2.9 

53.4 

0.63 

0.64 

1.27 

2.1 

< 0.076 

2.18 

6 

79.2 

<0.076 

79.2 

49.7 

3.6 

53.3 

2.4 

1.4 

3.8 

2.9 

1.0 

3.90 

7 

79.7 

<0.076 

79.7 

43.3 J 

3.8 

47.1 J 

0.76 

0.74 

1.5 

1.2 

0.51 

1.71 

8 

78.6 

<0.076 

78.6 

49.1 

3.3 

52.4 

1.3 

0.82 

2.12 

0.087 

< 0.076 

0.16 

9 

74.3 J 

<0.076 

74.3 J 

38.7 J 

4.6 J 

43.3 J 

0.65 J 

0.42 J 

1.07 J 

1.7 J 

< 0.076 

1.78 

10 

73.7 J 

<0.076 

73.7 J 

46.1 J 

2.9 J 

49.0 J 

0.72 J 

R 

NC 

1.6 J 

< 0.076 

1.68 

11 

73.7 

<0.076 

73.7 

48.5 

2.9 

51.4 

3.7 

2.3 

6.0 

6.2 

< 0.076 

6.28 

12 

72.4 

<0.076 

72.4 

42.0 

3.7 

45.7 

0.77 

0.92 

1.69 

2.2 

< 0.076 

2.28 

13 

73.4 

<0.076 

73.4 

42.2 

2.9 

45.1 

0.47 

0.87 

1.34 

1.6 

< 0.076 

1.68 

14 

71.4 

<0.076 

71.4 

43.0 

2.5 

45.5 

0.92 

0.86 

1.78 

1.7 

< 0.076 

1.78 

15 

72.2 

<0.076 

72.2 

39.9 

2.8 

42.7 

0.22 

0.77 

0.99 

1.5 

< 0.076 

1.58 

16 

73.6 

<0.076 

73.6 

45.2 

2.5 

47.7 

0.14 

1.0 

1.14 

0.57 

0.83 

1.40 

17 

72.4 

<0.076 

72.4 

41.6 

2.9 

44.5 

0.21 

0.79 

1.0 

0.097 

0.78 

0.88 

18 

69.8 

<0.076 

69.8 

41.3 

2.8 

44.1 

0.27 

0.91 

1.18 

0.14 

0.83 

0.97 

19 

71.0 

<0.076 

71.0 

43.8 

2.4 

46.2 

0.084 

0.97 

1.05 

< 0.056 

0.86 

0.92 

20 

72.2 

<0.076 

72.2 

43.3 

2.5 

45.8 

0.068 

0.69 

0.76 

< 0.056 

0.67 

0.73 

21 

71.0 

<0.076 

71.0 

41.1 

2.6 

43.7 

0.14 

0.93 

1.07 

1.4 

< 0.076 

1.48 

22 

71.5 

<0.076 

71.5 

42.8 

2.6 

45.4 

0.07 

1.1 

1.17 

1.8 

< 0.076 

1.88 

23 

69.7 

<0.076 

69.7 

43.0 

2.5 

45.5 

0.22 

1.3 

1.52 

1.8 

< 0.076 

1.88 

24 

69.6 

<0.076 

69.6 

39.8 

3.6 

43.4 

0.23 

1.0 

1.23 

1.6 

< 0.076 

1.68 

25 

68.9 

<0.076 

68.9 

39.1 

2.7 

41.8 

0.085 

1.1 

1.19 

0.13 

1.1 

1.23 

26 

69.1 

<0.076 

69.1 

40.9 

2.7 

43.6 

0.057 

1.2 

1.26 

< 0.056 

1.1 

1.16 

27 

69.2 

<0.076 

69.2 

19.3 

1.4 

20.7 

< 0.056 

0.88 

0.88 

1.46 

< 0.076 

1.54 

28 

67.9 

<0.076 

67.9 

42.4 

2.5 

44.9 

0.14 

1.3 

1.44 

0.57 

0.88 

1.45 

Mean 3 

74 J 

ND 

74 J 

43 J 

3.0 J 

46 J 

0.9 J 

1.0 J 

1.9 J 

1.7 J 

0.4 

2.1 


1 Represents a sample set in which samples from all four locations were collected at the approximate same time. 

2 Represents combined Nitrate-N and Nitrite-N in which values < the detection limit were considered zero for summing totals. 

3 Means are rounded to two significant digits. Values < detection limit considered zero for calculating means. 

J = Estimated value. R = Value rejected by QC. NC = Not calculated. ND = Not detected at or above MDL. 


37 







Table 4-6. Event 1 - Summary of Treatment Effectiveness. 


Sample 

Round’ 

1 

Nitrate-N/Nitrite-N Results (mg/I) 

Post BDN Final Effluent 

Total-N 2 Nitrate-N Nitrite-N Total-N 2 

Flow 

Final Effluent - 

MeOH TSS 

Other Performance Criteria 

Turbidity pH 3 Total Heterotrophs 

2.5 

2.5 

< 0.15 

2.65 

(gpm) 

(mg/i) 

91 

(mg/I) 

9 

(NTU) 

8.6 

(SU) 

7.7 / 8.6 

fCFU/mlf 

1,300/ NG 

2 

1.87 

2.2 

< 0.15 

2.35 

3.2 

— 

... 

--- 

... 

... 

3 

5.8 

5.3 

0.26 

5.56 

3.1 

— 

— 

— 

— 

... 

4 

5.1 

3.8 

1.3 

5.10 

3.1 

< 0.23 

9 

3.1 

7.7/8.2 

2,300 / 2,000,000 

5 

1.27 

2.1 

< 0.076 

2.18 

3.1 

... 

... 

... 

... 

... 

6 

3.8 

2.9 

1.0 

3.90 

0.02 4 

— 

— 

— 

— 

— 

7 

1.5 

1.2 

0.51 

1.71 

5.3 

< 0.23 

6 

3.1 

7.5/7.5 

NG/4,500,000 

8 

2.12 

0.087 

< 0.076 

0.16 

— 

... 

— 

... 

— 

... 

9 

1.07 J 

1.7 J 

< 0.076 

1.78 

— 

... 

... 

... 

... 

... 

10 

R 

1.6 J 

< 0.076 

1.68 

2.6 

5 

10.5 

5.2 

8.1 / 8.2 

— 

11 

6.0 

6.2 

< 0.076 

6.28 

2.8 

... 

... 

... 

... 

— 

12 

1.69 

2.2 

< 0.076 

2.28 

3.1 

3.4 

10 

4.8 

8.1 / 7.7 

— 

13 

1.34 

1.6 

< 0.076 

1.68 

2.9 

... 

... 

... 

... 

... 

14 

1.78 

1.7 

< 0.076 

1.78 

3.5 

7.8 

11.5 

5.0 

7.7/8.2 

NG / 670 

15 

0.99 

1.5 

< 0.076 

1.58 

3 

... 

... 

... 

... 

... 

16 

1.14 

0.57 

0.83 

1.40 

3 

... 

... 

-- 

... 

— 

17 

1.0 

0.097 

0.78 

0.88 

3.1 

< 0.23 

10 

2.0 

7.8/ 8.1 

3,200 / 3,200,000 

18 

1.18 

0.14 

0.83 

0.97 

2.8 

... 

... 

— 

— 

— 

19 

1.05 

< 0.056 

0.86 

0.92 

2.8 

— 

... 

... 

... 

— 

20 

0.76 

< 0.056 

0.67 

0.73 

2.9 

< 0.23 

11.3 

2.8 

7.8 / 8.3 

1,000 / 7,200,000 

21 

1.07 

1.4 

< 0.076 

1.48 

3 

— 

— 

— 

— 

— 

22 

1.17 

1.8 

< 0.076 

1.88 

3 

— 

— 

... 

-- 

— 

23 

1.52 

1.8 

< 0.076 

1.88 

3.2 

27 

10.5 

6.2 

7.7/8.2 

1,800/ 1,300 

24 

1.23 

1.6 

< 0.076 

1.68 

2.9 

... 

... 

... 

... 

... 

25 

1.19 

0.13 

1.1 

1.23 

3 

— 

... 

... 

... 

— 

26 

1.26 

< 0.056 

1.1 

1.16 

2.9 

< 0.23 

14.2 

2.8 

— 

— 

27 

0.88 

1.46 

< 0.076 

1.54 

2.9 

... 

... 

... 

... 

... 

28 

1.44 

0.57 

0.88 

1.45 

3 

26 

11 

4.8 

... 

... 

Mean 5 

1.9 J 

1.7 J 

0.4 

2.1 

3 

14.6 

10.3 

4.4 

7.5-8.6 

1,400/ 2,700,000 


' Represents a sample set in which samples from all four locations were collected at the approximate same time. 

2 Total-N is equal to the combined Nitrate-N + Nitrite-N concentration. 

J The first value represent the inlet water and the second value represents the final effluent. 

4 Flow rate value represents a likely interruption in the system followed by increased flow to compensate. 

5 All values, except for pH, are means, rounded to two significant digits. Values < detection limit considered zero when calculating means. 

R = Value rejected by QC. J = Estimated value. Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


38 














Table 4-7. Event 1 - Dissolved Oxygen Measurements (mg/I). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)’ 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

5-5-99 

1000-1100 

1 

9.76 

2.34 

6.17 

7.00 

5-5-99 

1600-1625 

2-3 

9.78 

1.10 

4.65 

6.78 

5-6-99 

0930 

4-6 

10.68 

1.10 

5.70 

6.35 

5-7-99 

1130 

7,8,9 

8.91 

1.02 

5.30 

6.90 

5-8-99 

1000 

10-11 

11.40 

0.92 

5.80 

5.90 

5-9-99 

1630 

12-13 

10.98 

0.95 

6.35 

7.95 

5-10-99 

0930 

14,15,16 

12.04 

1.05 

5.65 

7.15 

5-11-99 

2030 

17,18,19 

9.66 

0.65 

4.50 

4.52 

5-12-99 

0945 

20,21,22 

9.52 

1.28 

4.50 

4.20 

5-13-99 

0900 

23,24,25 

9.48 

1.00 

4.90 

5.35 

5-14-99 

0945 

26-27 

9.67 

0.91 

4.85 

5.02 

5-15-99 

- 0730 

28 

9.61 

0.72 

4.92 

5.90 

Mean 2 

10 

1.1 

5.3 

6.1 


1 Sample rounds conducted closest in time to the measurement are bolded. 2 Mean values are rounded to two significant digits. 


Table 4-8. Event 1 - pH Measurements. 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)' 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

5-5-99 

1000-1100 

1 

7.74 

7.81 

8.43 

8.61 

5-5-99 

1445-1500 

2-3 

7.67 

7.73 

8.24 

8.45 

5-6-99 

0727-1100 

4-6 

7.66 

7.66 

8.21 

8.21 

5-7-99 

1315-1330 

7,8,9 

7.50 

7.5 

7.2 

7.5 

5-8-99 

0758-0810 

10-11 

8.10 

7.58 

8.20 

8.23 

5-9-99 

1455-1510 

12-13 

8.07 

7.5 

7.5 

7.7 

5-10-99 

0837-0850 

14,15,16 

7.70 

7.79 

8.0 

8.20 

5-11-99 

0805-0825 

17,18,19 

7.79 

7.75 

8.05 

8.12 

5-12-99 

0832-0859 

20,21,22 

7.79 

7.78 

8.15 

8.25 

5-13-99 

0942-0955 

23,24,25 

7.65 

7.74 

8.12 

8.21 

5-14-99 

— 

26-27 

— 

— 

— 

... 

5-15-99 

— 

28 

— 

— 

— 

... 

Range 2 

7.5 -8.1 

7.5 -7.8 

7.2 -8.4 

7.5 -3.6 


' Sample rounds conducted closest in time to the measurement are bolded. 2 Range values are rounded to two significant digits 
Dashed line indicates that samples collected at the locations were not analyzed for that parameter. 


39 















































Table 4-9. Event 1- Turbidity Measurements (NTU). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)’ 

SAMPLE POINT 

Pass / 
Fail 2 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

5-5-99 

1000-1100 

1 

0.00 

— 

4.4 

8.6 

F 

5-6-99 

0727-1100 

4-6 

0.00 

0.00 

3.4 

3.10 

F 

5-7-99 

0941-0950 

7,8,9 

0.00 

0.00 

2.95 

3.13 

F 

5-8-99 

0835-0844 

10-11 

0.00 

0.00 

1.69 

5.15 

F 

5-9-99 

1555-1610 

12-13 

0.00 

0.00 

2.14 

4.81 

F 

5-10-99 

0752-0800 

14,15,16 

0.00 

0.00 

2.68 

5.03 

F 

5-11-99 

0758-0820 

17,18,19 

0.00 

0.00 

2.31 

2.00 

F 

5-12-99 

0847-0855 

20,21,22 

0.00 

0.00 

2.85 

2.82 

F 

5-13-99 

0847-0855 

23,24,25 

0.00 

0.00 

2.62 

6.18 

F 

5-14-99 

1005-1010 

26-27 

0.00 

0.00 

2.61 

2.75 

F 

5-15-99 

0715 

28 

0.00 

0.00 

3.63 

4.82 

F 

Mean 3 

0.00 

0.00 

2.8 

4.4 

0/11 


1 Sample rounds conducted closest in time to the measurement are bolded. 

2 A sample round is considered passing if the final effluent value is O NTU. In the last row, the number of passing values is shown in 
the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

3 Mean values are rounded to two significant digits. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


determine if final effluent met the goal of < 1 normal 
turbidity units (NTU) (Objective 3). The readings indicate 
turbidity to be measured consistently above that goal 
each day of sampling and to average 4.4 NTU. 

The TSS data in Table 4-10 provide information on the 
amount of solids added to the inlet water by the BDN 
process during Event 1. More importantly, the laboratory- 
derived TSS data can be used in conjunction with the field 
turbidity measurements to assess the effectiveness of the 
post-treatment system for removing those solids. The data 
show the inletwater to be essentially free of TSS (i.e., only 
one value was above the MDL). As would be expected, 
the post-treatment chlorination used during Event 1 had no 
effect on the increased TSS levels produced during BDN. 
The average post BDN and final effluent values were 
essentially the same (12 mg/I and 10 mg/I, respectively). 
On a per round basis, all final effluent values were greater 
than their paired inlet water values. 

The Event 1 microbial results presented in Table 4-11 
include data for the three separate types of microbial 
analyses conducted: TCH, FA, and FC. Inletwater, post 
BDN, and final effluent outfalls were sampled for these 
parameters. 

The results of the TCH analyses can be used to measure 
the additional bacteria produced by EcoMat’s BDN process 


(relative to inlet water) and to determine how effective the 
post-treatment system was for removing the increased 
level of bacteria. The data indicated that the TCH 
population associated with the BDN process effluent was, 
on average, three orders of magnitude higher than TCH 
levels in the well water. The carryover of this bacteria from 
the BDN process to the final effluent was measured, on 
average, to exceed 100 percent. Final effluent TCH values 
were measured to be less than corresponding inlet water 
TCH values in only two of the seven sampling rounds. 

The FA analyses provide a useful measure of the 
production of active biodenitrifying bacteria during the BDN 
process. The concentration of these bacteria in inlet water 
gives some indication of the character and quality of the 
well water. Their numbers would be expected to greatly 
increase in the post-BDN effluent and then greatly 
decrease in final effluent due to post-treatment. 

The FA data followed the expected pattern only to a certain 
degree. The average of the FA plate count mean in inlet 
water was increased by three orders of magnitude in post 
BDN effluent. However, the post-treatment effectiveness 
for reducing FA in final effluent was inconsistent. Final 
effluent plate count means for individual samples ranged 
from < 1000 cfu/ml to > 800,000 cfu/ml. The final effluent 


40 
























Table 4-10. Event 1- TSS Results (mg/I). 


Sample Round 
No. 

SAMPLE POINT 

Pass / 
Fail 1 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

1 

< 5 

— 

15.2 

9 

F 

4 

< 5 

— 

7.5 

9 

F 

7 

< 5 

— 

8 

6 

F 

10 

5.5 

— 

14.7 

10.5 

F 

12 

< 5 

— 

9.5 

10 

F 

14 

< 5 

— 

12.7 

11.5 

F 

17 

< 5 

— 

12 

10 

F 

20 

< 5 

— 

13.3 

11.3 

F 

23 

< 5 

— 

14 

10.5 

F 

26 

< 5 

— 

12.7 

14.2 

F 

28 

< 5 

— 

14 

11 

F 

Mean 2 

< 5 

... 

12 

10 

0/11 


1 A sample round is considered passing if the final effluent value is <^the inlet water value. In the last row, the number of passing 
values is shown in the numerator, the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit are considered zero when calculating means. 


mean value was less than the inlet water mean value for 
only one sample round. 

A possible contributing factor to the high variability of post¬ 
treatment performance on FA could have been the lack of 
controlled chlorination. At least on one occasion during 
Event 1, the chlorine tablets being used were completely 
depleted without being replenished for an indefinite time 
period. This lapse was recorded to occur a couple of hours 
after round #20 samples were collected and almost a day 
before round #23 samples were collected. Round #20 and 
the preceding round #17 had the two poorest results with 
respect to large percentage increases in FA as measured 
from post-BDN to final effluent (i.e., > 100 % carryoverfrom 
BDN); whereas for round #23 the final effluent was 
measured to have had less than 6% of the post-BDN plate 
count mean. 

The FC analyses can be used to compare the quality of the 
inlet water with final effluent. Ideally, there should be no 
increase. Since fecal coliform are aerobic, they could 
become dormant during the BDN process and difficult to 
measure among the other bacteria. For Event 1, there was 
no growth of FC measured in inlet water, nor was there any 
growth for the post-BDN and final effluent streams. 

Table 4-12 presents the Event 1 laboratory results for 
methanol analyses conducted on inlet water, post-BDN 
effluent, and final effluent. There were small detectable 
concentrations of methanol in three of the eleven inlet 
watersamples. Round #1 results indicate that initially there 


may have been a larger than expected imbalance in the 
methanol-nitrate ratio, causing excess methanol in the 
post-BDN effluentto carry overto the final effluent. For all 
subsequent test samples, methanol was not detectable in 
the post-BDN effluent, indicating that most of the carbon 
source had been used up in the BDN process. There is no 
explanation why detectable concentrations of methanol 
were measured in five of the final effluent samples 
corresponding to the post-BDN samples showing no 
detectable concentrations of methanol. The post-treatment 
chlorination was primarily used as a disinfectant and 
should not have impacted methanol concentrations. 

Table 4-13 presents the results of supplemental analyses 
that were carried out on a limited number of samples to 
obtain general background information on the technology. 
These analyses included VOCs, total metals, sulfate, 
alkalinity, total solids, phosphate, ammonia, and total 
organic carbon (TOC). 

CCI 4 , which had been historically detected in PWS Well #1 
water, was not detected in the inlet water sample nor in 
effluent samples. A small concentration of the VOC 
chloroform, which is a also a trihalomethane (THM), was 
detected in the final effluent. It is possible that chloroform 
is a reaction by-product of CCI 4 and chlorine in the 
presence of organic matter. 

The majority ofthe supplementalanalyses results indicates 
the BDN and post-treatment systems to have little to no 
effect on the measured parameters. The increase in TOC 


41 






















Table 4-11. Event 1 - Microbial Results. 


Sample 

Round 

No. 

Inlet 

Water 2 


Post 

BDN 2 


Final 

Effluent 2 

1 

1,300 

90,000 

NG 

4 

2,300 

29,800 

2,000,000 

7 

NG 

28,000 

4,500,000 

14 

NG 

15,000 

670 

17 

3,200 

4,500,000 

3,200,000 

20 

1,000 

11,300,000 

7,200,000 

23 

1,800 

680,000 

1,300 

Avg. 

1,400 

2,400,000 

2,700,000 

FACULTATIVE ANAEROBES - F 

1 

23,000 


150,000 


6,600 

4 

4,600 

17,000,000 

620,000 

7 

3,500 

5,300,000 

350,000 

14 

250 

810,000 

... 

16 

... 

... 

330 

17 

280 

380,000 

810,000 

20 

260 

360,000 

480,000 

23 

440 

1,300,000 

76,000 

Avg. 

4,600 

3,600,000 

335,000 


TOTAL CULTURABLE HETEROTROPHS - Plate Count Mean (cfu/ml) 2 


FECAL COLIFORM (Fecal coliforms/IOOml) 


1 

NG 

4 

NG 

7 

NG 

14 

NG 

17 

NG 

20 

NG 

23 

NG 

Avg. 

NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


NG 


% Carryover 
from BDN 

% Change from 
Inlet Water 

Pass / 

Fail 3 

0 % 

- 100 % 

P 

6,700 % 

+ 870 % 

F 

16,000 % 

NC 

F 

4.5 % 

NC 

F 

71 % 

+ 1,000 % 

F 

64 % 

+ 7,200 % 

F 

0.2 % 

- 28 % 

P 

113 % 

+ 19,000 % 

2/7 

ate Count Mean (cfu/ml) 2 

4.4 % 

- 71 % 

P 

3.6 % 

+ 13,000 % 

F 

6.6 % 

+ 9,900 % 

F 

... 

... 

... 

NC 

NC 

... 

213% 

+ 290,000 % 

F 

133 % 

+ 190,000 % 

F 

5.8 % 

+ 17,000 % 

F 

9.3 % 

+ 7,300 % 

1/6 


NC 

NC 

— 

NC . 

NC 

— 

NC 

NC 

... 

NC 

NC 

— 

NC 

NC 

— 

NC 

NC 

— 

NC 

NC 

— 

NC 

NC 

... 


’ Post-treatment for Event 1 consisted solely of chlorination. 

2 Plate count mean = average of three separate analyses, reported in colony forming units per milliliter. 

3 A sample round is considered passing if the final effluent value is < the inlet water value. In the last row for each parameter, the number 
of passing values is shown in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the 
denominator. 

NG = No growth; for purposes of percent change calculations, it is assumed that this value is zero. 

NC = Not calculated; when the initial reading to be used in a calculation indicated no growth, no calculation was performed. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


42 



































































































































Table 4-12. Event 1- Methanol Results (mg/I). 


Sample 

SAMP 

LE POINT 

Pass/ 

Round 

Mo 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

Fail 1 

1 

1 

... 

64 

91 

F 

4 

< 0.23 

... 

< 0.23 

< 0.23 

P 

7 

__ 

... 

< 0.23 

< 0.23 

P 

10 

2.5 

_ 

< 0.23 

5 

F 

12 

< 0.23 


< 0.23 

3.4 

F 

14 

< 0.23 

... 

< 0.23 

7.8 

F 

17 

< 0.23 

... 

< 0.23 

< 0.23 

P 

20 

3.9 

... 

< 0.23 

< 0.23 

P 

23 

< 0.23 

— 

< 0.23 

27 

F 

26 

< 0.23 

... 

< 0.23 

< 0.23 

P 

28 

< 0.23 

__ 

< 0.23 

26 

F 

Mean 2 

0.7 

... 

5.8 

15 

5/11 


1 A sample round is considered passing if the final effluent value is < 1 mg/I. In the last row, the number of passing values is shown 


in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit are considered zero when calculating means. 
Da shed line indicates that sam pies collected at that loca tion were not analyzed for that param eter. 


Table 4-13. Event 1 - Supplemental Analyses Results (mg/I). 1 


Sample 

Round 

Analyte 2 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

7,14, 20 

CCL 

< 0.001 

_ 

< 0.001 

<0.001 

7,14,20 

Chloroform 

< 0.001 

_ 

< 0.001 

0.006 

7,14, 20 

Total Solids 

855 

_ 

602 

635 

7,14, 20 

Ammonia 

< 0.8 

_ 

< 0.8 

< 0.8 

7.14, 20 

Total Organic Carbon 

1.2 

... 

6.47 

6.07 

7,14, 20 

Sulfate 

106* 

... 

102 

104 

7,14, 20 

Phosphate 

< 0.082* 

_ 

1.21 

— 

7,14, 20 

Alkalinity 

166 

... 

373 

367 


Metals 

7,14, 20 

Barium 

0.08 

... 

0.074 

0.073 

7,14. 20 

Calcium 

150 

... 

130 

130 

7,14,20 

Potassium 

1.8 

— 

1.8 

1.8 

7,14, 20 

Magnesium 

42 

— 

42 

42 

7,14, 20 

Sodium 

12 

— 

13 

14 

7.14,20 

Phosphorus _ 

_<MZ_ 

— 

_ Ml _ 

_ 0.65 


1 Values are the mean of the three test results (except where indicated) and are rounded to a maximum three significant digits. 

2 Exceptfor CCI 4 only The SW-846 Method 8260 contaminants with mean values above detection limits are reported. 

Metals analyzed for included Ag, Al, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Sb, and Zn. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter; and no pass/fail determination was made. 
* Two samples collected only. 


43 



















































following BDN is likely attributable to the carryover of 
biological material and methanol. The increased alkalinity 
following BDN is consistent with the slight increase in pH 
(refer to Table 4-8). The small amount of phosphate and 
phosphorus measured in the effluent samples is residuum 
from the 50% methanol solution, which contains food grade 
phosphoric acid. 

4.4.1.5 Mass Removal of Nitrate 

The percent mass removal of nitrate, as measured as 
Nitrate-N, was estimated for Event 1 (Objective 4). A total 
of approximately 42,000 gallons, orabout 160,000 liters of 
well water was treated during Event 1. Each mg/I of nitrate- 
N is equivalent to 4.4 mg/I of nitrate. Since the mean 
nitrate-N concentration for Event 1 inlet water was 74 mg/I, 
the total mass of nitrate treated during Event 1 would be 
(74 x 4.4) mg/I x 160,000 liters = 52,000,000 mg. The mean 
nitrate-N concentration for Event 1 final effluent was 1.7 
mg/I. The total mass of nitrate in the final effluent = (1.7 x 
4.4) mg/I x 160,000 liters = 1,200,000 mg. Therefore, the 
mass removal of nitrate during Event 1 would be 


approximately 52,000,000 mg - 1,200,000 mg = 51,000,000 
mg (a 98% reduction in nitrate). This would correlate to 
51,000 grams or 112 pounds. However, the contribution of 
nitrite should not be discounted since it can be re¬ 
converted to nitrate. Including the nitrite that remains in the 
final effluent, the mass removal would be 111 pounds. 

4.4.1.6 System Performance Vs. Flow Rate 

The performance of EcoMat’s combined BDN and post¬ 
treatment system components were evaluated with respect 
to water flow through the system (Objective 2). The 
variation in inlet water flow rate during Event 1 was 
compared with the total-N concentrations in the final 
effluent. Figure 4-4 directly compares the Event 1 
fluctuation for inlet water flow rate to the Event 1 fluctuation 
in total-N final effluent concentrations forthe same sample 
rounds. There is a similar pattern to both of the plots that 
suggests a relationship between flow rate and BDN 
effectiveness (i.e., lower flow rates corresponding to more 
effective BDN). This is evident where the somewhat sharp 
decrease in flow rate occurred about one quarter the way 



44 









through the event correlates to a sharp reduction in total-N 
concentration. However, elsewhere during the event there 
are variations in the total-N values that cannot be 
correlated with fluctuations in flow; these may correspond 
to upsets in the treatment process. The plots in Figure 4- 
4 also indicate that once the system was kept at a 
consistent flow rate (i.e., the average event flow rate of 3 
gpm), the BDN performance remained stable and quite 
effective. 


4.4.2 Event 2 

4.4.2.1 Summary 

Event 2 was a 10-day sampling episode conducted August 
3-12, 1999. During Event 2, a total of 31 sampling rounds 
were conducted and ~ 45,000 gallons of nitrate- 
contaminated well water passed through EcoMat’s 
treatment system at an average flow rate of 3.5 gpm. 
Based on this average flow rate, and on an estimated 
retention capacity of 1,300 gallons for the reactor tanks, 
sampling rounds were normally conducted four times per 
day at approximately 6V2 hour intervals. 

Figure 4-5 separately illustrates the effectiveness of the 
EcoMat BDN and post-treatment systems evaluated during 



so 



20 



INLET 
WATER 
(from WS 
VMrffi) 



Event 2. The nitrate-N in PWS Well #1 had a mean 
concentration of 68 mg/I during the second event. This 
mean inlet water concentration was slightly less than for 
Event 1 (74 mg/I), possibly due to inflow of clean water into 
the aquifer as contaminated water was removed. During 
the partial BDN treatment process that occurred in the first 
reactor (R1), the nitrate-N levels were reduced by about 
40%, with a small amount of nitrite remaining from the 
nitrate to nitrite conversion. Subsequent treatment in the 
EcoMat Reactor (R2) further reduced the nitrate-N 
concentration from a mean of 41 mg/I to a mean of 4.6 
mg/I. The mean nitrite-N concentration increased from 
1mg/l to 1.5 mg/I between partial BDN and post-BDN 
samples. A mean total-N concentration of 6.1 mg/I was 
attained by the BDN treatment for Event 2 samples. 

During Event 2 post-treatment consisted of an initial 
separation of suspended solids in a clarifying tank 
(“clarification”), followed by sand and cartridge filtration and 
finally by UV oxidation. The post-treatment had no effect on 
nitrite-N concentrations and only a minimal effect on 
nitrate-N concentrations. The mean values for total-N 
concentrations for post-BDN and final effluent samples 
were 6.1 mg/I and 5.6 mg/I, respectively. 


Event 2 

Flow @ 3.5 gpm 
Legend 

42 ■ Total-N concentration (mg/1) 

(41/1) = Nitrate-N / Mbrtte-N concentration (mg/Q 

BDN = Biodenitrification 

ND = Not detected > detection limits 


POST BDN 
TREATMENT 

(R2 Effluent) 


8.1 

(4.6/1.5) 


{> 


Post 

Treatment 
(see below) 


FINAL 

EFFLUENT 

4 > 5.6 

(4.1/1.5) 


Event 2 Post-Treatment Effectiveness 


Post BDN 

MeOH = 88 
TSS = 13 
Turbidity = 4.7 
TCH = 2.9x10* 
FC = 51 
FA = 8x10* 


4 



4 


Final Effluent 

MeOH = 98 
TSS = < 5 
Turbidity = 1.8 
TCH = 1.8 x 10 7 
FC = 42 
FA =3.2x10* 


Figure 4-5. Event 2 - Treatment Effectiveness for Averaged Test Results. 


45 











































4.4.2.2 Event 2 Statistical Analysis 

The summary statistics for the critical measurements are 
presented in Table 4-14. Nitrate-N, nitrite-N, and total-N 
results for the four sampling locations for all 31 sample 
rounds comprising Event 2 are shown in Table 4-15. The 
mean valuesfrom this data were used in generating Figure 
4-5. This data was also used to evaluate the Primary 
Objective (Objective 1 ). 


Table 4-14. Event 2 - Summary Statistics. 

Critical 

Measurement 

Mean 

(mg/I) 

Median 

(mg/I) 

Standard 

Deviation 

(mg/I) 

Post BDN 

Total-N 

6.145 

4.600 

3.781 

Final Effluent 
Nitrate-N 

4.132 

2.220 

4.237 

Final Effluent 
Nitrite-N 

1.459 

1.200 

1.155 


The EDA indicated that the data from Event 2 more closely 
resembled a lognormal than a normal distribution. When 
Shapiro-Wilk tests were run, both normality and 
lognormality were rejected for all measurements exceptthe 
final effluent nitrite-N data, which fit a lognormal 
distribution. However, the presence of one extreme point 
may have biased the results. Therefore, the non- 
parametric WSR was chosen for analyzing all of the data 
and the median was used as the appropriate measure of 
central tendency. 

Statistical hypothesis tests thatwere conducted yieldedthe 
following results: 

• Part I: Post BDN median total-N of 4.60 mg/I was 
significantly below the criterion of 10.5 mg/I. 

• Part II: Final Effluent met all criteria. The median 
nitrate-N, nitrite-N, and total-N concentrations 
were 2.22, 1.20, and 3.61 mg/I, respectively. 
These values were below their respective criterion 
of 10.5, 1.5, and 10.5 mg/I. 

Based on the results of these 2 hypothesis tests, Event 2 
was shown to be successful in reducing levels of nitrite-N 
and nitrate-N to below regulatory limits. 

4.4.2.3 General Evaluation of BDN System 

Table 4-16 presents a summary of all performance criteria 
results for Event 2. This includes the post-BDN and final 
effluent nitrate-N, nitrite-N, and total-N data for each ofthe 
31 Event 2 tests. Also included are the additional analytical 
data and field measurement results that were used for 


evaluating other performance criteria. On a per round 
basis, the objectives regarding reductions in nitrate-N, 
nitrite-N, and total-N in the final effluent were attained for 
17 of the 31 sample rounds. Other performance criteria 
results shown in Table 4-16 indicate the need for more 
substantial post-treatment, especially for treating residual 
methanol and removing microbial matter. 

The daily DO measurements in Table 4-17 show that for 
approximately the first half of the event (i.e., rounds 1-14) 
the daily measured DO in the partially treated BDN effluent 
was consistently above 1 mg/I. Then, for the remainder of 
the event, DO was consistently below 1 mg/I. The 
deoxygenating process was effective in reducing the mean 
inlet water DO of approximately 9 mg/I down to 
approximately 1 mg/I in partially treated water exiting the 
Deoxygenating Tank. 

4.4.2.4 General Evaluation of Post-Treatment System 

The field and laboratory measurements used primarily for 
evaluating the post-treatment component of EcoMat’s 
Process during Event 2 (Objective 5) included pH; turbidity; 
TSS; microbial analyses; methanol; and “supplemental 
analyses”. 

The daily pH measurements in Table 4-18 indicate a very 
slight increase in alkalinity from inlet water to post BDN 
effluent. However, there was essentially no change in pH 
range in the final effluent following post-treatment. 

The daily turbidity measurements in Table 4-19 indicate 
turbidity to be consistently above the secondary drinking 
water criterion of 1 NTU. However, the mean NTU of 1.8 
was much improved over the Event 1 turbidity results. 

The TSS data in Table 4-20 show that the inlet water 
contain no detectable levels ofTSS and post BDN effluent 
to contains, on average, 13 mg/I of TSS. The final effluent 
data indicated the post-treatment system had a positive 
effect on reducing TSS levels, on average to less than 5 
mg/I, most likely due to filtration. Six of nine final effluent 
values were less than their paired inlet water values. 

Table 4-21 presents the laboratory results for Total TCH, 
FC, and FA at each of the four outfalls. An additional 
sample was collected immediately upstream of the UV 
oxidation unit and analyzed for TCH and FC to evaluate 
that unit independently of the remainder of the post¬ 
treatment system (refer back to Figure 4-5). 

The results of the TCH analyses indicated that the TCH 
population associated with the BDN process was, on 
average .three orders of magnitude higher than TCH levels 
in the well water. On average, approximately 6 percent of 
this bacteria carried over from the BDN process to the final 
effluent. This marked a substantial improvement from the 
first Event when no filtration was used. However, all seven 
final effluent TCH values were measured to be above the 


46 
















Table 4-15. Event 2 - Nitrate-N and Nitrite-N Results (mg/I). 


Sample 


Inlet Water 



Partial BDN 



Post BDN 


Final Effluent 

Round 1 














Nitrate- 

Nitrite- 

Total- 

Nitrate- 

Nitrite- 

Total- 

Nitrate- 

Nitrite- 

Total- 

Nitrate- 

Nitrit 

Total- 


N 

N 

N 2 

N 

N 

N 2 

N 

N 

N 2 

N 

e-N 

N 2 

1 

71.5 

< 0.076 

71.5 

54.1 

0.29 

54 4 

6.6 

0.34 

6.9 

5.2 

0.37 

5.6 

2 

71.3 

< 0.076 

71.3 I 

58.7 

0.17 

58.9 

14.4 

0.52 

14.9 

13.2 

0.48 

13.7 

3 

71.4 

< 0.076 

71.4 

32.4 

0.73 

33.1 

6.8 

0.72 

7.5 

10.8 

0.94 

11.7 

4 

72.0 

< 0.076 

72.0 

42.6 

0.22 

42 8 

11.9 

0.19 

12.1 

9.6 

0.28 

9.9 

5 

71.5 

< 0.076 

71.5 

53.4 

0.21 

53.6 

12.5 

0.88 

13.4 

11.1 

0.79 

11.9 

6 

72.9 

< 0.076 

72.9 

27.1 

1.7 

28.8 

12.3 

6 

18.3 

18.6 

6.7 

25.3 

7 

73.1 

< 0.076 

73.1 

49.1 

0.69 

49 8 

4.6 

1.5 

6.1 

4.1 

1.7 

5.8 

8 

73.1 

< 0.076 

73.1 

45.4 

0.74 

46.1 

4 

0.94 

4.9 

2.8 

0.81 

3.6 

9 

67.0 

< 0.076 

67.0 

41.2 

0.85 

42.1 

2.7 

0.82 

3.5 

1.2 

0.74 

1.9 

10 

65.6 

< 0.076 

65.6 

42.8 

0.99 

43.8 

1.8 

0.77 

2.6 

1.5 

0.76 

2.3 

11 

66.5 

< 1.9 

66.5 

36 

< 1.9 

36 

3 

1.6 

4.6 

2.2 

1.6 

3.8 

12 

69.3 

< 0.076 

69.3 

43.3 

0.86 

44.2 • 

3.34 

1.52 

4.9 

1.7 

0.95 

2.7 

13 

68.7 

< 0.076 

68.7 

47.2 

1.16 

48.4 

4.8 

2.11 

6.9 

2.54 

1.8 

4.3 

14 

68.5 

< 0.076 

68.5 

38.1 

1.37 

39.5 

2.42 

0.813 

3.2 

1.34 

0.73 

2.1 

15 

69.8 

< 0.076 

69.8 

41.4 

1.3 

42.7 

2.9 

1.6 

4.5 

3.5 

1.9 

5.4 

16 

69.8 

< 0.076 

69.8 

49.3 

0.99 

50.3 

6.3 

2.6 

8.9 

6.0 

2.8 

8.8 

17 

67.5 

< 0.076 

67.5 

47.2 

0.99 

48.2 

5.8 

2.9 

8.7 

6.1 

2.9 

9.0 

18 

67.5 

< 0.076 

67.5 

41 

1.5 

42.5 

4 

2.1 

6.1 

3.5 

2.1 

5.6 

19 

66.7 

< 0.076 

66.7 

38.3 

1.3 

39.6 

3.1 

1.8 

4.9 

3.1 

1.9 

5.0 

20 

64.4 

< 0.076 

64.4 

38.4 

1.4 

39.8 

2.8 

1.5 

4.3 

2.1 

1.4 

3.5 

21 

65.2 

< 0.076 

65.2 

37.8 

1.5 

39.3 

2 

1.4 

3.4 

1.1 

0.99 

2.1 

22 

63.2 

< 0.076 

63.2 

41.3 

1.3 

42.6 

3.7 

1.9 

5.6 

3.1 

1.8 

4.9 

23 

64.0 

< 0.076 

64.0 

37.8 

1.3 

39.1 

2.2 

1.2 

3.4 

1.5 

1.0 

2.5 

24 

65.7 

< 0.076 

65.7 

39.1 

1.1 

40.2 

2.7 

1.4 

4.1 

1.7 

1.3 

3.0 

25 

66.1 

< 0.076 

66.1 

37.8 

1.1 

38.9 

2.7 

1.5 

4.2 

1.5 

1.3 

2.8 

26 

66.2 

< 0.076 

66.2 

35.6 

1.4 

37.0 

2.5 

1.6 

4.1 

2.1 

1.5 

3.6 

27 

67.0 

< 0.076 

67 

38.4 

1.1 

39.5 

2.5 

1.5 

4.0 

1.7 

1.4 

3.1 

28 

65.7 

< 0.076 

65.7 

36.2 

1.2 

37.4 

2.2 

1.3 

3.5 

1.6 

1.1 

2.7 

29 

67.2 

< 0.076 

67.2 

35.7 

1.4 

37.1 

2.4 

1.4 

3.8 

1.5 

1.2 

2.7 

30 

67.6 

< 0.076 

67.6 

35.3 

1.3 

36.6 

2.2 

1.4 

3.6 

0.9 

1.0 

1.9 

31 

66.4 

< 0.076 

66.4 

34.5 

1.4 

35.9 

2.2 

1.3 

3.5 

1.2 

0.98 

2.2 

Mean 3 

68 

ND 

68 

41 

1.0 

42 

4.6 

1.5 

6.1 

4.1 

1.5 

5.6 


' Represents a sample set in which samples from all four locations were collected at the approximate same time. 

2 Represents combined Nitrate-N and Nitrite-N. Values < the detection limit were considered 0.0 when summing totals. 

3 Means are rounded to two significant digits. Values < detection limit are considered zero when calculating means. 

ND = Not detected at or above MDL. 


47 













Table 4-16. Event 2 - Summary of Treatment Effectiveness. 


Sample 

Nitrate-N/Nitrite-N Results (mg/I) 

Post Final Effluent 

Flow 

Final Effluent 

MeOH TSS 

- Other Performance Criteria 

Turbidity pH 2 Total Heterotrophs 2 

Round’ 

Total-N’ 

Nitrate- 

Nitrite-N 

Total-N' 

(gp m ) 

(mg/I) 

(mg/I) 

(NTU) 

(SU) 

(CFU/ml) 

1 

6.9 

5.2 

0.37 

5.6 

— 

— 

— 

— 

— 

... 

2 

14.9 

13.2 

0.48 

13.7 

2.9 

... 

... 

— 

... 

. ... 

3 

7.5 

10.8 

0.94 

11.7 

2.5 

34 

5.6 

2.7 

7.8/7.6 

5,000 / 380,000 

4 

12.1 

9.6 

0.28 

9.9 

3.1 

... 

... 

... 

... 

... 

5 

13.4 

11.1 

0.79 

11.9 

3.9 

... 

... 

— 

... 

— 

6 

18.3 

18.6 

6.7 

25.3 

4.4 

... 

... 

... 

... 

— 

7 

6.1 

4.1 

1.7 

5.8 

3.4 

70 

6 

2.6 

8.2 / 7.9 

27,000 / 3,300,000 

8 

4.9 

2.8 

0.81 

3.6 

2.9 

— 

... 

— 

— 

— 

9 

3.5 

1.2 

0.74 

1.9 

2.7 

... 

— 

— 


— 

10 

2.6 

1.5 

0.76 

2.3 

2.7 

— 

... 

— 

7.4/7.8 

— 

11 

4.6 

2.2 

1.6 

3.8 

3.2 

180 

< 5 

2.3 

... 

17,000 / 250,000 

12 

4.9 

1.7 

0.95 

2.6 

3.5 

... 

... 

... 

... 

... 

13 

6.9 

2.5 

1.8 

4.4 

1.6 

110 

< 5 

2.4 

7.5/7.8 

— 

14 

3.2 

1.3 

0.73 

2.1 

2.6 

... 

— 

... 

... 

— 

15 

4.5 

3.5 

1.9 

5.4 

3.3 

... 

... 

... 

... 

... 

16 

8.9 

6.0 

2.8 

8.8 

4.7 

39 

< 5 

1.6 

7.5/8.2 

28,000 / 620,000 

17 

8.7 

6.1 

2.9 

9.0 

4.5 

... 

— 

... 

... 

— 

18 

6.1 

3.5 

2.1 

5.6 

... 

94 

< 5 

1.2 

7.6 / 8.4 

33,000/ 130,000 

19 

4.9 

3.1 

1.9 

5.0 

... 

... 

— 

... 

... 

— 

20 

4.3 

2.1 

1.4 

3.5 

4 

... 

... 

... 

... 

— 

21 

3.4 

1.1 

0.99 

2.1 

3.7 

— 

... 

... 

7.6 / 7.7 

— 

22 

5.6 

3.1 

1.8 

4.9 

— 

100 

< 5 

1.1 

— 

370,000 / 25,000,000 

23 

3.4 

1.5 

1.0 

2.5 

4 

... 

... 

... 

... 

— 

24 

4.1 

1.7 

1.3 

3.0 

3.9 

— 

... 

... 

... 

... 

25 

4.2 

1.5 

1.3 

2.8 

4 

— 

... 

... 

... 

... 

26 

4.1 

2.1 

1.5 

3.6 

3.9 

77 

9 

1.2 

7.4/8.3 

230,000 / 97,000,000 

27 

4.0 

1.7 

1.4 

3.1 

3.9 

... 

— 

... 

— 

— 

28 

3.5 

1.6 

1.1 

2.7 

3.6 

... 

... 

... 

... 

— 

29 

3.8 

1.5 

1.2 

2.7 

3.8 

— 

... 

— 

— 

— 

30 

3.6 

0.9 

1.0 

1.9 

3.8 

180 

< 5 

1.5 

7.4 / 8.2 

— 

31 

3.5 

1.2 

0.98 

2.2 

3.8 

... 

... 

— 

... 

— 

Mean 2 

6.1 

4.1 

1.5 

5.6 

3.5 

98 

< 5 

1.8 

7.4-8.4 

100,000/ 18,000,000 


1 Total-N is equal to the combined Nitrate-N + Nitrite-N concentration. 

2 The first value represent the inlet water and the second value represents the final effluent. 

3 AII values, except for the pH range, are means rounded to two significant digits. Values < detection limit are considered zero when calculating means. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


48 













Table 4-17. Event 2 - Dissolved Oxygen Measurements (mg/I). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s ) 1 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

8-4-99 

0945-1015 

2-3,4,5 

— 

1.65 

5.88 

2.11 

8-5-99 

1000-1054 

6-7,8,9 

8.70 

1.78 

5.90 

4.55 

8-6-99 

0900-1000 

10-11,12 

8.74 

1.14 

5.89 

0.51 

8-7-99 

0820-0842 

13,14 

9.45 

1.45 

5.61 

1.03 

8-8-99 

1440-1523 

15,16 

8.85 

0.72 

6.14 

5.9 

8-9-99 

0830-0955 

17-18,19,20 

9.33 

0.61 

6.30 

4.30 

8-10-99 

0845-0950 

21-22,23,24 

8.8 

0.5 

5.90 

4.64 

8-11-99 

0800-0837 

25,26,27,28 

9.09 

0.5 

6.30 

3.55 

8-12-99 

0830 

29-30,31 

8.81 

0.67 

5.40 

0.5 

Mean 2 

9.0 

1.0 

5.9 

3.0 


' Sample rounds conducted closest in time to the measurement are bolded. 

2 Mean values are rounded to two significant digits. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-18. Event 2 - pH Measurements. 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)’ 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

8-4-99 

0920-1016 

2-3,4,5 

7.76 

7.5 

7.62 

7.61 

8-5-99 

0956-1054 

6-7,8,9 

8.18 

7.72 

7.72 

7.91 

8-6-99 

0919-1006 

10-11,12 

7.35 

7.57 

8.01 

7.82 

8-7-99 

0821-0843 

13,14 

7.45 

7.25 

7.91 

7.84 

8-8-99 

1445-1524 

15,16 

7.48 

7.39 

8.19 

8.19 

8-9-99 

0855-0956 

17-18,19,20 

7.56 

7.75 

8.46 

8.38 

8-10-99 

0921-0934 

21-22,23,24 

7.64 

7.67 

8.39 

8.38 

8-11-99 

0804-0830 

25,26,27,28 

7.44 

7.61 

8.36 

8.32 

8-12-99 

0915-0925 

29-30,31 

7.39 

7.58 

8.25 

8.2 

Range 2 

7.4 -8.2 

7.4 -7.8 

7.6 -8.5 

7.6 -8.4 


1 Sample rounds conducted closest in time to the measurement are bolded. 

2 Range values are rounded to two significant digits. 


49 







































Table 4-19. Event 2 -Turbidity Measurements (NTU). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)' 

SAMPLE POINT 

Pass/ 

Fail 2 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

8-4-99 

0931-1018 

2-3,4,5 

0.45 

0.95 

8.3 

2.7 

F 

8-5-99 

1003-1056 

6-7,8,9 

0.30 

0.35 

4.7 

2.6 

F 

8-6-99 

0925-1008 

10-11,12 

0.15 

0.85 

7.2 

2.3 

F 

8-7-99 

0825-0845 

13,14 

0.0 

0.9 

7.6 

2.4 

F 

8-8-99 

1448-1526 

15,16 

0.45 

0.25 

2.7 

1.6 

F 

8-9-99 

0855-0958 

17-18,19,20 

0.0 

0.3 

5.0 

1.2 

F 

8-10-99 

0921-0953 

21-22,23,24 

0.05 

0.4 

4.5 

1.1 

F 

8-11-99 

0804-0843 

25,26,27,28 

0.00 

0.25 

2.2 

1.2 

F 

8-12-99 

0915-0925 

29-30,31 

0.00 

0.5 

0.5 

1.5 

F 

Mean 3 

0.16 

0.53 

4.7 

1.8 

0/9 


' Sample rounds conducted closest in time to the measurement are bolded. 

2 A sample round is considered passing if the final effluent is <1 NTU. In the last row, the number of passing values is shown in the 
numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

3 Mean values are rounded to two significant digits. Values < detection limit considered zero when calculating means. 


Table 4-20. Event 2 - TSS Results (mg/I). 


Sample 
Round No. 

SAMPLE POINT 

Pass/ 

Fail 1 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

3 

< 5 

... 

23 

5.6 

F 

7 

< 5 

... 

17.1 

6 

F 

11 

< 5 

... 

11 

< 5 

P 

13 

< 5 

... 

8 

< 5 

P 

16 

< 5 

... 

10.4 

< 5 

P 

18 

< 5 

... 

12 

< 5 

P 

22 

< 5 

... 

13.3 

< 5 

P 

26 

< 5 

... 

17.8 

9 

F 

30 

< 5 

... 

< 5 

< 5 

P 

Mean 2 

< 5 

— 

13 

< 5 

6/9 


1 A sample round is considered passing if the final effluent value is < the inlet water value. In the last row, the number of passing values 
is shown in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit considered zero when calculating means. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


50 








































Table 4-21. Event 2 - Microbial Results. 1 


Sample 

Round 

No. 

TOTAL CULTURABLE HETEROTROPHS - Plate Count Mean (cfu/ml) 2 

Inlet 
Water 2 


Post 

BDN 2 


Final 

Effluent 2 


% Carryover 
from BDN 

% Change from 
Inlet Water 

Pass / 
Fail 3 

3 

5,000 

7,300,000 

380,000 


5.2 % 

+ 7,600 % 

F 

7 

27,000 

117,000,000 

3,300,000 


2.8 % 

+' 12,000 % 

F 

11 

17,000 

33,000,000 

250,000 


0.8 % 

+ 1,500 % 

F 

16 

28,000 

880,000,000 

620,000 

V : 

0.7 % 

+ 2,200 % 

F 

18 

33,000 

420,000,000 

130,000 

0.03 % 

+ 390 % 

F 

22 

370,000 

470,000,000 

25,000,000 

fpl 

5.4 % 

+ 6,800 % 

F 

26 

230,000 

97,000,000 

97,000,000 

100 % 

+ 42,000 % 

F 

Avg. 

101,000 

289,000,000 

18,100,000 

6.3 % 

+ 18,000 % 

0/7 

FACULTATIVE ANAEROBES - Plate Count Mean (cfu/ml) 2 

3 

2,900 


360,000 


85,000 


24 % 

+2,800 % 

F 

7 

3,100 

760,000 

70,000 

9.2 % 

+ 2,200 % 

F 

11 

320 

320,000 

150,000 

if 

53 % 

+ 47,000 % 

F 

16 

220 

11,000,000 

37,000 

M 

0.3 % 

+ 17,000 % 

F 

18 

520 

9,600,000 

3,600,000 


38 % 

+ 690,000 % 

F 

22 

2,400 

19,000,000 

11,000,000 

m 

58 % 

+ 460,000 % 

F 

26 

3,400 

15,000,000 

7,400,000 

49 % 

+ 220,000 % 

F 

Avg. 

1,840 

8,000,000 

3,190,000 


40 % 

+ 170,000 % 

0/7 

FECAL COLIFORM (Fecal coliforms/IOOml) 

3 

232 


135 


NG 

a 

0 % 

- 100 % 

P 

7 

190 

22 

173 

790 % 

-9.1 % 

P 

11 

335 

2 

28 

1,400 % 

- 92 % 

P 

16 

278 

62 

88 

140% 

- 32 % 

P 

18 

27 

2 

NG 

0 % 

- 100 % 

P 

22 

73 

28 

3 


11 % 

- 96 % 

P 

26 

62 

105 

3 


2.9 % 

- 95 % 

P 

Avg. 

170 

51 

42 

§§ 

82 % 

- 75 % 

7/7 


1 Post-treatment for Event 2 consisted of clarification, followed by sand filtration, cartridge filtration, and UV oxidation. 

2 Plate count mean = average of three separate analyses, reported in colony forming units per milliliter. 

3 A sample round is considered passing if the final effluent value is < the inlet water value. In the last row, the number of passing 
values is shown in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 
NG = No growth. 

NC = Not calculated. 


51 






























































































































corresponding inlet water values. Thus, the secondary 
criterion was not met for TCH. The pre-UV oxidation mean 
value for TCH was two orders of magnitude lowerthan the 
final effluent plate count mean average, indicating that the 
clarification and filtration preceding UV oxidation may have 
been the only effective post-treatment. Based on the limited 
results, UV was, at best, non-effective and, at worst, 
detrimental with respect to TCH treatment. It is not clear 
whether the UV oxidation system was correctly sized for 
the role or whether other factors adversely affected its 
utility. 

As was the case with Event 1, the FA data followed the 
expected pattern to a certain degree. The average of the 
FA plate count means for inlet water increased by three 
orders of magnitude in post BDN effluent. The post¬ 
treatment effectiveness was improved over Event 1, but 
was inconsistent. Final effluent plate count means for 
individual sample rounds ranged from 37,000 cfu/ml to 
11,000,000 cfu/ml. None of the final effluent mean values 
was less than the inlet water mean value. Thus, the 
secondary criterion was not met for FA. The sharp 
increase (i.e., two orders of magnitude) for final effluent FA 
values, starting midway through Event 2, could have been 
the result of filter breakthrough. 

For Event 2, the FC values in final effluent were below inlet 
water values, both on a per round and total average basis. 
Thus, the secondary criterion was met for FC. The pre-UV 
oxidation sample indicated UV oxidation to haveno positive 

Table 4-22. Event 2- Methanol Results (mg/I). 


effect on FC (refer back to Figure 4-5). 

The methanol results in Table 4-22 indicate that methanol 
was not detected in inlet water samples, but was detected 
in all post BDN and final effluent samples. The mean 
methanol concentrations in post BDN and final effluent 
were 88 and 98 mg/I, respectively. The post BDN and final 
effluent values were also very similaron a per round basis, 
indicating that the UV oxidation post-treatment had no 
effect on reducing residual methanol concentrations. The 
secondary criterion of < 1 mg/I was, therefore, not met for 
any of the sample rounds. 

Table 4-23 presents results of supplemental analyses for 
all outfalls sampled. The majority of these results indicate 
thatthe BDN and post-treatment systems to had little to no 
effect on the measured parameters. The mean 
concentration of CCI 4 detected in the inlet water during 
Event 2 was small (i.e., 1.4 pg/l). CCI 4 was not detected in 
effluent samples. This indicates that the compound was 
either volatilized or biodegraded during the BDN process. 
The only other VOC detected was chloroform, which was 
measured at a low concentration in the final effluent. 

The somewhat significant increase in TOC following BDN 
can be attributed to the carryover of biological material 
and/or methanol. The increased alkalinity following BDN is 
consistent with the slight increase in pH (refer to Table 4- 
18). The small amounts of phosphate and phosphorus 
measured in effluent samples is residuum from the 50% 


Sample Round 
No. 

SAMPLE POINT 

Pass/ 

Fail 1 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

3 

< 0.23 

— 

46 

34 

F 

7 

<0.23 

— 

73 

70 

F 

11 

< 0.23 

_ 

160 

180 

F 

13 

< 0.23 

... 

90 

110 

F 

16 

< 0.23 

... 

21 

39 

F 

18 

< 0.23 

... 

60 

94 

F 

22 

<0.23 

... 

100 

100 

F 

26 

< 0.23 

... 

68 

77 

F 

30 

< 0.23 

— 

170 

180 

F 

Mean 2 

< 0.23 

... 

88 

98 

0/9 


' A result is considered passing if the final effluent value is < 1 mg/I. In the last row, the number of passing values is shown in the 
numerator; the total number of values is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit considered zero for calculating means. 

NG = No growth. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


52 




















Table 4-23. Event 2 - Supplemental Analyses Results (mg/I). 1 


SAMPLE 
ROUND NOs. 

Analyte 2 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

7 , 16 , 26 

CCI, 

< 0.0014 

_ 

<0.001 

<0.001 

7 , 16,26 

Chloroform 

< 0.001 

... 

<0.001 

0.002 

7 , 16 , 26 

Total Solids 

877 

___ 

612 

600 

7 , 16 , 26 

Ammonia 

< 0.8 

... 

< 0.8 

< 0.8 

7 , 16 , 26 

Total Organic Carbon 

1.1 

— 

47 

45 

7 , 16 , 26 

Sulfate 

80 

— 

77 

76 

7 . 16 , 26 

Phosphate 

< 0.082 

... 

1.2 

... 

7 , 16 , 26 

Alkalinity 

162 

... 

374 

370 



7 , 16 , 26 

Barium 

0.078 

... 

0.073 

0.072 

7 , 16 , 26 

Calcium 

130 

_ 

123 

123 

7 , 16 , 26 

Potassium 

1.8 

— 

1.7 

1.6 

7 , 16 , 26 

Magnesium 

37 

— 

37 

38 

7 , 16 , 26 

Sodium 

12 

__ 

13 

13 

_ 7 , 16 , 2 $_ 

_ Phosphorus _ 

< 0.35 

... 

1.3 

1.3 


1 Values are the Mean of the three test results and are rounded to a maximum three significant digits. 

2 Except for CCI 4 only SW-846 Method 8260 contaminants with mean values above detection limits are reported. 

Metals analyzed for included Ag, Al, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Sb, and Zn. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


methanol solution, which contains food grade phosphoric 
acid. 

4.4.2.5 Mass Removal of Nitrate 

The percent mass removal of nitrate, measured as Nitrate- 
N, was estimated for Event 2 (Objective 4). A total of 
approximately 45,000 gallons, or about 170,000 liters of 
well water was treated during Event 2. Each mg/I of nitrate- 
N is equivalent to 4.4 mg/I of nitrate. Since the mean 
nitrate-N concentration for Event 2 inlet water was about 68 
mg/I, the total mass of nitrate treated during Event 2 would 
be (68 x 4.4)mg/l x 170,000 liters = 51,000,000 mg. The 
mean nitrate-N concentration for Event 2 final effluent was 
4.1 mg/I. The total mass of nitrate in the final effluent = (4.1 
x 4.4) mg/I x 170,000 liters = 3,000,000 mg. Therefore the 
mass removal of nitrate during Event 2 would be 
approximately 52,000,000 mg - 3,000,000 mg = 49,000,000 
mg (a 94% reduction in nitrate). This correlates to 49,000 
grams or 108 pounds. Adding the nitrite-N in the final 
effluent would reduce the removal by 2 pounds. 


4.4.2.6 System Performance Vs. Flow Rate 

The performance of EcoMat’s combined BDN and post¬ 
treatment system components were evaluated with respect 
to water flow through the system (Objective 2). The 
variation in inlet water flow rate during Event 2 was 
compared with the total-N concentrations in the final 
effluent. Figure 4-6 directly compares the Event 2 
fluctuation for inlet water flow rate to the Event 2 fluctuation 
in total-N final effluent concentrations throughout the 
duration of Event 2. As was the case with the first event 
the flow rate and final effluent total-N concentrations 
patterns are similar to one another; although there was a 
lot more variability during the first half of the event testing. 
Nonetheless, the inverse relationship showing lower flow 
rates consistent with increased BDN effectiveness is still 
apparent. Similar to Event 1 a rather sharp decrease in 
flow rate occurred about one quarter the way through the 
event and correlated to a sharp reduction in total-N 
concentration. The plot in figure 4-6 also indicates that the 
system became stabilized past the halfway point of Event 
2. Once again, other operating factors may mask the 
expected correlation of flow and denitrification. 


53 
































Figure 4-6. Event 2 - Comparison of Flow Rate Fluctuations and Final Effluent Total N-Concentrations. 


4.4.3 Event 3 

4.4.3.1 Summary 

Event 3 was a 9-day sampling episode conducted October 
20-28, 1999. During Event 3, a total of 30 sampling rounds 
were conducted and ~ 49,000 gallons of nitrate- 
contaminated well water passed through EcoMat’s 
treatment system at an average flow rate of 4 gpm. Flow 
rates among the individual sampling rounds varied 
considerably, ranging between -2 and 7 gpm. Based on 
the average flow rate, and an estimated retention capacity 
of 1,300 gallons forthe reactor tanks, the sampling rounds 
were normally conducted three times per day. However, 
due to the high variability in flow rate, the sample rounds 
were conducted at intervals anywhere between 3-7 hours 
apart. 

Figure 4-7 illustrates the effectiveness of the EcoMat BDN 
and post-treatment systems used for Event 3. The mean 
nitrate-N concentration in PWS Well #1 during Event 3 
was 38 mg/I. This concentration was significantly less than 


that measured for Event 2, which occurred approximately 
2Vz months earlier. During the partial BDN in the first 
reactor (R1), the mean nitrate-N levels were reduced by 
about 47%, with a small amount of nitrite generated by the 
nitrate to nitrite conversion. Subsequent treatment in the 
EcoMat reactor (R2) further reduced the mean nitrate-N 
concentration from of 20 mg/I to 7.7 mg/I. The average 
nitrite-N concentration increased from 1.3 mg/I to 2.9 mg/I 
between partial and post-BDN samples. Mean total-N 
effluentconcentration of approximately 11mg/l was attained 
by the BDN treatment for Event 3 samples. 

Event 3 post-treatment consisted of ozone followed by UV 
oxidation followed by clarification. Clarification was followed 
by “rough" filtration, “high efficiency” filtration, carbon 
adsorption, and “polishing” filtration. The post-treatment 
system had no effect on nitrate-N or nitrite-N levels. When 
rounded to two significant digits, the mean total-N 
concentrations for post-BDN and final effluent samples 
were - 11 mg/I and 9.9 mg/I, respectively. 


54 










60 


40 


£ 

Jf 

i 


20 


INLET 

WATER 

(frwn PWS 
Wallfl) 


PARTIAL BDN 
TREATMENT 
(R1 Effluent) 



Event 3 

Flow @4.1 gpm 
Legend 

21 = Total-N concentration (mg/I) 
(20/13) = Nitrate N / Nitrite-N concentration (mg/D 

BDN = Biodenitrification 

ND - Not detected > detection limits- 


R2 

EcoMat 

Reactor 


POST BDN 

TREATMENT 
(R2 EffluenQ 

11 rv 


(77/2.9) 


Post 

Treatment 
(See below) 


FINAL 

EFFLUENT 


-£> 

^ (8.3/1.6) 


Post BDN 

MeOH = 41 
TSS = < 5 
Turbidity = 1.3 
TCH = 6.7 x 10 6 
FC = 50 
FA = 6x10 s 


Event 3 Post-Treatment Effectiveness 



Figure 4-7. Event 3 - Treatment Effectiveness for Averaged Test Results. 


Final Effluent 


MeOH = 41 
TSS = < 5 
Turbidity = 1.2 
TCH = 6.9 x10 s 
FC = 5 

FA = 1,7 x10 s 


4.4.3.2 Event 3 Statistical Analysis 

The summary statistics for the critical measurements are 
presented in Table 4-24. Nitrate-N, nitrite-N, and total-N 
results for the four sampling locations for all 30 Event 3 
sample rounds are shown in Table 4-25. The mean values 
from these data were to evaluate the primary objective 
(Objective 1) and for generating Figure 4-7. 


Table 4-24. Event 3 - Summary Statistics. 

Critical 

Measurement 

Mean 

(mg/I) 

Median 

(mg/1) 

Standard 
Deviation (mg/I) 

Post BDN Total-N 

10.613 

10.950 

3.706 

Final Effluent 
Nitrate-N 

8.347 

8.350 

2.854 

Final Effluent 
Nitrite-N 

1.545 

1.400 

0.851 

Final Effluent 

Total-N 

9.897 

9.825 

2.978 


The EDA indicated that the data from Event 3 closely 
resembled a normal distribution, except for the post BDN 
data. When Shapiro-Wilk tests were run, normality was 
accepted for all variables except the post BDN data. For 
these data neither the normal nor lognormal distribution 
was shown to fit the data. Therefore, the non-parametric 
WSR was chosen for analyzing the post BDN data and the 
median was used as the appropriate measure of central 
tendency. The Student’s t-test was chosen for analyzing 
the other three measurements (i.e., final effluent nitrate-N, 
final effluent nitrite-N, and final effluent total-N), thus the 
mean was used as the appropriate measure of central 
tendency. 

Statistical hypothesis tests thatwere conducted yielded the 
following results: 

• Part I: For the Post BDN total-N data, both the 

mean of 10.613 mg/I and the median of 10.950 
mg/I were above the criterion of 10.5 mg/I. Thus, 
no statistical test was needed to determine that the 
Post BDN data did not meet that criterion. 


55 

























































Table 4-25. Event 3 - Nitrate-N and Nitrite-N Results (mg/I). 




Inlet Water 



Partial BDN 



Post BDN 



Final Effluent 


Sample 

Round' 

Nitrate- 

N 

Nitrite- 

N 

Total- 

N 2 

Nitrate- 

N 

Nitrite- 

N 

Total- 

N 2 

Nitrate- 

N 

Nitrite- 

N 

Total- 

N 2 

Nitrate- 

N 

Nitrite- 

N 

Total- 

N 2 

1 

43.9 

< 0.076 

43.9 

10 

1.4 

11.4 

3.9 

4.0 

7.9 

1.7 

0.44 

2.14 

2 

41.8 

< 0.076 

41.8 

22.3 

1.7 

24 

6.4 

2.6 

9.0 

5.3 

0.85 

6.15 

3 

44.1 

< 0.076 

44.1 

19.9 

1.4 

21.3 

6.4 

3.0 

9.4 

8.9 

0.95 

9.85 

4 

45.7 

< 0.076 

45.7 

23.7 

1.8 

25.5 

6.6 

2.0 

8.6 

7.6 

<0.076 

7.6 

5 

45.3 

< 0.076 

45.3 

22.4 

1.8 

24.2 

12 

3.0 

15 

13.3 

1.1 

14.4 

6 

41.8 J 

< 0.076 

41.8 J 

18.7 

1.7 

20.4 

6.7 

3.2 

9.9 

9.4 

1.1 

10.5 

7 

41.1 

< 0.076 

41.1 

21.6 

1.5 

23.1 

10.1 

2.8 

12.9 

9.9 

1.1 

11 

8 

41.8 

< 0.076 

41.8 

7.6 

1.8 

9.4 

7.2 

3.4 

10.6 

11 

1.4 

12.4 

9 

40.3 

< 0.076 

40.3 

17.3 

3.0 

20.3 

10.5 

2.8 

13.3 

8.2 

1.3 

9.5 

10 

40.4 

< 0.076 

40.4 

23.9 

0.74 

24.6 

7.5 

2.5 

10 

7.4 

1.1 

8.5 

11 

38.5 

< 0.076 

38.5 

26.9 

0.96 

27.9 

12.5 

2.9 

15.4 

12.2 

1.3 

13.5 

12 

40.3 

< 0.076 

40.3 

27.1 

1.1 

28.2 

12.2 

3.7 

15.9 

12.6 

2.5 

15.1 

13 

38.9 

< 0.076 

38.9 

26.3 

1.1 

27.4 

12.1 

3.7 

15.8 

12.7 

2.4 

15.1 

14 

39.0 

< 0.076 

39.0 

24.6 

1.1 

25.7 

11.4 

3.7 

15.1 

11.8 

2.1 

13.9 

15 

38.7 

< 0.076 

38.7 

23.7 

0.88 

24.6 

9.2 

1.8 

11 

9.1 

3.5 

12.6 

16 

36.9 

< 0.076 

36.9 

22.3 

0.89 

23.2 

8.8 

3.3 

12.1 

8.6 

1.8 

10.4 

17 

36.8 

< 0.076 

36.8 

22.5 

0.77 

23.3 

8.5 

3.1 

11.6 

7.8 

2.0 

9.8 

18 

37.3 

< 0.076 

37.3 

14.4 

0.76 

15.2 

<.056 

0.19 

0.19 

5.4 

1.5 

6.9 

19 

36.8 

< 0.076 

36.8 

24.1 

0.66 

24.8 

8.7 

2.2 

10 

8.4 

0.84 

9.24 

20 

37.1 

< 0.076 

37.1 

25 

0.63 

25.6 

10.1 

2.9 

13 

11.1 

1.1 

12.2 

21 

36.6 

< 0.076 

36.6 

23 

0.69 

23.7 

9.6 

3.2 

12.8 

6.6 

1.4 

8.0 

22 

35.4 

< 0.076 

35.4 

22.4 

0.88 

23.3 

8.9 

3.7 

12.6 

9.1 

1.6 

10.7 

23 

35.5 

< 0.076 

35.5 

21.8 

0.78 

22.6 

8.3 

3.4 

11.7 

8.3 

<0.076 

8.3 

24 

35.3 

< 0.076 

35.3 

20 

0.91 

20.9 

7.0 

3.2 

10.2 

9.4 

0.38 

9.78 

25 

34.8 

< 0.076 

34.8 

14.1 

2.9 

17 

4.5 

2.5 

7.0 

5.5 

3.0 

8.5 

26 

34.7 

< 0.076 

34.7 

10 

3.0 

13 

2.5 

2.6 

5.1 

2.5 

2.6 

5.1 

27 

33.7 

< 0.076 

33.7 

13.3 

1.9 

15.2 

8.0 

3.0 

11 

7.8 

2.6 

10.4 

28 

33.6 

< 0.076 

33.6 

15.2 

1.7 

16.9 

4.8 

3.3 

8.1 

5.2 

2.5 

7.7 

29 

32.7 

< 0.076 

32.7 

7.5 

0.99 

8.49 

0.15 

1.2 

1.35 

5.6 

1.9 

7.5 

30 

31.4 

< 0.076 

31.4 

19 

0.8 

19.8 

7.4 

3.0 

10.4 

8.0 

2.0 

10 

Mean 2 

38 J 

ND 

38 J 

20 

1.3 

21 

7.7 

2.9 

11 

8.4 

1.5 

9.9 


1 Represents a sample set in which samples from all four locations were collected at the approximate same time. 

2 Represents combined Nitrate-N and Nitrite-N. Values below the detection limit were considered 0.0 when summing totals. 

3 Means are rounded to two significant digits. Values < detection limit considered zero when calculating means. 

J = Estimated value. ND = Not detected at or above MDL. 


56 







• Part II: Final Effluent did not meet its performance 

estimate since the nitrite-N mean was above the 
1.5 mg/I criterion. 

Based on the results of these 2 hypothesis tests, Event 3 
was not shown to be successful in reducing levels of nitrite- 
N and nitrate-N to below regulatory limits. 

4.4.3.3 General Evaluation of BDN System 

Table 4-26 presents the post-BDN and final effluentnitrate- 
N; the nitrite-N; and total-N results for the four sampling 
points for each of the 30 Event 3 sampling rounds. Also 
included in Table 4-26 are additional analytical data and 
field measurement results that were used for evaluating 
other performance criteria. A total of 11 of the 30 sample 
rounds showed reductions in nitrate-N, nitrite-N, and total- 
N in the final effluent to below the respective regulatory 
criteria (when the results are rounded to the nearest whole 
number). Results for other performance criteria indicated 
a steady improvement in mean turbidity values with 
substantially less biological carryover than in the first two 
events. However, those same results indicated thatneither 
the ozone nor the UV oxidation treatment was effective in 
reducing mean residual methanol concentrations to below 
1 mg/I. 

The daily DO measurements in Table 4-27 showed DO in 
the partially treated BDN effluent to be consistently above 
1 mg/I and to average slightly over 2 mg/I for the entire 
event. Although the deoxygenating process was effective 
in reducing mean inlet water DO of 9.5 mg/I down to - 2 
mg/I, the elevated DO values are an indicator that 
anaerobic processes were not optimized. This was a likely 
contributing factor to the poorer performance of Event 3 
with respect to nitrate-N and nitrite-N reduction. Also, the 
addition of ozone as a post-treatment step did not 
significantly increase the DO of the final effluent. 

4.4.3.4 General Evaluation of Post-Treatment System 

The field and laboratory measurements used primarily for 
evaluating the post-treatment component of the EcoMat’s 
Process during Event 3 (Objective 5) included pH, turbidity, 
TSS, microbial analyses, residual methanol, and 
“supplemental analyses". 

The daily pH measurements in Table 4-28 showed little to 
no change between all four sample points. Potential pH- 
altering post-treatment units used during Event 3, such as 
ozone, apparently had no impact on pH. 

The daily turbidity measurements in Table 4-29 indicate 
that although just two of nine final effluent values were 
measured below the secondary drinking water criteria of 1 
NTU, the 1.2 mean value of NTU in the final effluent 
showed continued improvement from Events 1 and 2. 

The TSS data in Table 4-30 showed that the inlet water 


contained no detectable levels of TSS and the post BDN 
effluent to contain detectable levels of TSS in six of the 
nine rounds. The final effluent data indicated that the post¬ 
treatment system had a positive effect on reducing TSS 
levels in all but one of those rounds, and that the final 
effluent mean TSS value was below the detection limit. 
Two of nine final effluent values were higher than their 
paired inlet water value. Thus, the secondary criteria was 
met for seven of nine rounds. Therefore, the combination 
of filters used for Event 3 was, for the most part, effective. 

Table 4-31 presents the laboratory results for Total TCH, 
FC, and FA at each of the four outfalls. An additional 
sample was collected immediately upstream of the UV 
oxidation unit and analyzed for TCH and FC to evaluate 
that post-treatment system independently of ozone 
treatment (refer to Figure 4-7). 

The results of the TCH analyses indicated the TCH 
population associated with the BDN process was, on 
average, two orders of magnitude higher than TCH levels 
in the well water. On average, approximately 10 percentof 
this bacteria carried over from the BDN process to the final 
effluent (similar to that measured for Event 2). And, like 
Event 2, all seven final effluent TCH values were measured 
to be above their paired inlet water values. Thus, the 
secondary criterion was not met for TCH. 

The pre-UV oxidation mean value for TCH (obtained from 
the added sample point upstream of the UV oxidation unit) 
was the same order of magnitude as the average of the 
mean inlet water values. Therefore, the ozone treatment 
may not have had any effect on TCH. The post-treatment 
train downstream of the ozone unit may have had all of the 
impact for reducing TCH levels in final effluent. 

Like the two previous events, the FA data generally 
followed the expected pattern of greatly increasing in the 
post-BDN effluent and then greatly decreasing in final 
effluent due to post-treatment (the values for round # 23 
were an exception). The average of the FA plate count 
mean values in inlet water was increased by one order of 
magnitude in post BDN effluent. The post-treatment 
effectiveness was improved over both previous events, but 
the results were skewed by the unexplainable final effluent 
mean value for round # 23. Only one of the final effluent 
mean values was less than the corresponding inlet water 
mean value. Thus, the criterion was not met for FA. (It 
should also be noted that the inlet water in round #19 
exhibited an unusually high FA). 

For Event 3, a small amount of FC was measured in final 
effluent of round 1 only. There was no FC measured in the 
paired inlet water sample for round 1. Conversely, there 
was FC measured in the last inlet water sample collected 
(round 30). A similar number of colonies was measured in 
the corresponding post BDN sample, but no FC was 
measured in the final effluent. On a per round basis the 


57 



Table 4-26. Event 3 - Summary of Treatment Effectiveness. 



Nitrate-N/Nitrite-N Results (mg/I) 



Final Effluent 

- Other Performance 

Criteria 

Sample 

Round 1 

Post BDN 

Total-N 

Nitrate-N 

Final Effluent 

Nitrite-N 

Total-N 2 

Flow 

MeOH 

TSS 

Turbidity 

pH 3 

Total Heterotrophs 3 

1 

7.9 

1.7 

0.44 

2.14 

(9Pm) 

(mg/D 

59 

(mfl/l) 

< 5 

(NTU) 

1.4 

(SU) 

8.1 / 7.9 

(CFU/ml) 

46,000/310,000 

2 

9.0 

5.3 

0.85 

6.15 

3.9 

... 

— 

... 

... 

... 

3 

9.4 

8.9 

0.954 

9.85 

4.4 

... 

... 

... 

... 

... 

4 

8.6 

7.6 

<0.076 

7.6 

2 

32 

< 5 

1.1 

8.1 / 8.2 

... 

5 

15 

13.3 

1.1 

14.4 

5 

... 

--- 

... 

... 

42,000 / 360,000 

6 

9.9 

9.4 

1.1 

10.5 

3.6 

... 

... 

... 

... 

— 

7 

12.9 

9.9 

1.1 

11 

5 

... 

— 

... 

... 

... 

8 

10.6 

11 

1.4 

12.4 

4.3 

... 

... 

... 

... 

— 

9 

13.3 

8.2 

1.3 

9.5 

4.9 

62 

< 5 

1.0 

8.1 / 8.0 

18,000/ 110,000 

10 

10 

7.4 

1.1 

8.5 

3.6 

... 

... 

... 

— 

— 

11 

15.4 

12.2 

1.3 

13.5 

4.6 

— 

... 

... 

... 

— 

12 

15.9 

12.6 

2.5 

15.1 

4.9 

... 

... 

... 

... 

... 

13 

15.8 

12.7 

2.4 

15.1 

4.7 

27 

< 5 

0.64 

8.2/8.0 

... 

14 

15.1 

11.8 

2.1 

13.9 

5.7 

... 

... 

— 

... 

— 

15 

11 

9.1 

3.5 

12.6 

4.3 

... 

— 

... 

— 

... 

16 

12.1 

8.6 

1.8 

10.4 

4.7 

... 

... 

— 

... 

... 

17 

11.6 

7.8 

2.0 

9.8 

4.3 

35 

5 

1.0 

8.1 / 8.0 

... 

18 

0.19 

5.4 

1.5 

6.9 

2.3 

... 

... 

... 

... 

... 

19 

10 

8.4 

0.84 

9.24 

4.8 

34 

7 

1.8 

8.2 / 8.0 

180,000 / 630,000 

20 

13 

11.1 

1.1 

12.2 

5 

--- 

... 

... 

... 

— 

21 

12.8 

6.6 

1.4 

8 

4.6 

... 

... 

... 

... 

... 

22 

12.6 

9.1 

1.6 

10.7 

4.5 

... 

... 

... 

... 

... 

23 

11.7 

8.3 

<0.076 

8.3 

4.5 

54 

< 5 

1.1 

... 

17,000/49,000 

24 

10.2 

9.4 

0.38 

9.78 

7.2 

— 

... 

— 

... 

— 

25 

7.0 

5.5 

3.0 

8.5 

3.3 

— 

... 

— 

— 

— 

26 

5.1 

2.5 

2.6 

5.1 

4 

... 

— 

... 

... 

... 

27 

11 

7.8 

2.6 

10.4 

5 

30 

< 5 

1.9 

8.1 / 8.1 

14,000/240,000 

28 

8.1 

5.2 

2.5 

7.8 

5.2 

... 

— 

... 

— 

... 

29 

1.35 

5.6 

1.9 

7.5 

3.3 

— 

— 

... 

... 

... 

30 

10.4 

8 

2.0 

10 

4.8 

33 

< 5 

0.84 

8.2/8.1 

120,000/3,200,000 

Mean 4 

11 

8.4 

1.5 

9.9 

4.2 

41 

< 5 

1.2 

7.9-8.2 

63.000 / 690,000 


' Represents a sample set in which samples from all four locations were collected at the approximate same time. 

2 Total-N is equal to the combined Nitrate-N + Nitrite-N concentration. 

3 The first value represent the inlet water and the second value represents the final effluent. 

4 All values, except for the pH range, are means rounded to two significant digits. Values < detection limit considered zero for calculating means. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


58 














Table 4-27. Event 3 - Dissolved Oxygen Measurements (mg/I). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)' 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

10-20-99 

1300 

1,2,3 

9.20 

1.90 

3.9 

4.88 

10-21-99 

1100 

4,5,6,7 

9.18 

1.91 

3.24 

8.67 

10-22-99 

0800 

8,9,10,11 

9.18 

1.91 

0.6* 

7.90 

10-23-99 

0900 

12-13,14 

9.25 

2.56 

4.1 

1.2 3 

10-24-99 

1400 

15,16,17 

10.0 

2.59 

3.74 

0.44 

10-25-99 

1045 

18-19,20,21 

9.62 

2.62 

2.10 

6.51 

10-26-99 

1630 

24,25 

— 

— 

— 

— 

10-27-99 

1130 

26,27,28,29 

9.37 

1.66 

2.65/0.2* 

3.21 

10-28-99 

0800 

30 

10.3 

1.66 

2.22 

3.68 

Mean 2 

9.5 

2.1 

3.1/0.4 

4.6 


’ Sample Rounds conducted closest in time to the measurement are boldec. 

2 Mean values are rounded to two significant digits. 

3 Average of two readings. 

* Measurement taken inside R2 tank due to air bubbles in hose. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-28. Event 3 - pH Measurements. 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.)’ 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

10-20-99 

1300 

1,2,3 

8.08 

8.09 

8.15 

7.93 

10-21-99 

1100 

4,5,6,7 

8.05 

7.94 

8.15 

8.17 

10-22-99 

0800 

8,9,10,11 

8.09 

8.03 

8.16 

8.03 

10-23-99 

0900 

12-13,14 

8.22 

8.12 

8.17 

8.00 

10-24-99 

1400 

15,16,17 

8.10 

8.06 

8.17 

7.98 

10-25-99 

1045 

18-19,20,21 

8.19 

8.03 

8.15 

8.02 

10-26-99 

1630 

24,25 

— 

— 

... 

... 

10-27-99 

1130 

26,27,28,29 

8.11 

8.14 

8.21 

8.10 

10-28-99 

0800 

30 

8.15 

8.06 

8.18 

8.06 

Range 2 

8.1 -8.2 

7.9 -8.1 

8.2 -8.2 

7.9 -8.2 


1 Sample rounds conducted closest in time to the measurement are bolded. 

2 Range values are rounded to two significant digits. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


59 











































Table 4-29. Event 3 - Turbidity Measurements (NTU). 


DATE 

TIME 

INTERVAL 

Associated 

Round(s)' 

SAMPLE POINT 

Pass/ 
Fail 2 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

10-20-99 

1300 

1,2,3 

— 

--- 

— 

1.4 

F 

10-21-99 

1100-1400 

4,5,6,7 

0.13 

0.38 

1.20 

1.07 

F 

10-22-99 

0800-0900 

8,9,10,11 

0.10 

0.65 

2.14 

1.03 

F 

10-23-99 

0900 

12-13,14 

0.32 

0.39 

0.86 

0.64 

P 

10-24-99 

1400 

15,16,17 

0.18 

1.38 

1.10 

1.02 

F 

10-25-99 

1045 

18-19,20,21 

0.65 

— 

1.51 

1.82 

F 

10-26-99 

1630 

24,25 

0.17 

1.60 

1.09 

1.06 

F 

10-27-99 

1130 

26,27,28,29 

0.21 

— 

1.67 

1.86 

F 

10-28-99 

0800 

30 

0.15 

4.25 

0.95 

0.84 

P 

Mean 3 

0.24 

1.4 

1.3 

1.2 

2/9 


1 Sample rounds conducted closest in time to the measurement are bolded. 

2 A round is considered passing if the final effluent is < 1 NTU. In the last row, the number of passing values is shown in the numerator; 
the total number of values (pass + fail, minus any blank values) is shown in the denominator 

3 Mean values are rounded to two significant digits. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-30. Event 3 -TSS Results (mg/I). 


Sample 
Round No. 

SAMPLE POINT 

Pass/ 

Fail ’ 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

1 

< 5 

... 

6 

< 5 

P 

4/5 

< 5 

... 

5 

< 5 

P 

9 

< 5 

... 

6 

< 5 

P 

13 

< 5 

... 

< 5 

< 5 

P 

17 

< 5 

... 

< 5 

5 

F 

19 

< 5 

... 

5 

7 

F 

23 

< 5 

... 

5.3 

< 5 

P 

27 

< 5 

... 

8 

< 5 

P 

30 

< 5 

... 

< 5 

< 5 

P 

Mean 2 

< 5 

... 

< 5 

< 5 

7/9 


' A round is considered passing if the final effluent value is < the inlet water value. In the last row, the number of passing values is 
shown in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit considered zero when calculating means. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


60 







































Table 4-31. Event 3 - Microbial Results. 1 


Sample 

Round 

No. 

TOTAL CULTURABLE HETEROTROPHS - Plate Count Mean (cfu/ml) 2 

Inlet 
Water 2 


Post 

BDN 2 


Final 

Effluent 2 

Iff 

v- < 

<>: 

% Carryover 
from BDN 

% Change from 
Inlet Water 

Pass / 
Fail 3 

1 

46,300 

3,100,000 

305,000 

9.8 % 

+ 660 % 

F 

5 

42,000 

7,550,000 

362,000 

4.8 % 

+ 860 % 

F 

9 

17,700 

3,370,000 

113,000 


3.4 % 

+ 640 % 

F 

19 

183,000 

5,150,000 

632,000 


12 % 

+ 350 % 

F 

23 

17,300 

4,230,000 

49.000 4 


1.2 % 

+ 280 % 

F 

27 

14,200 

21,300,000 

240,000 

1.1 % 

+ 1,690 % 

F 

30 

120,000 

1,970,000 

3,160,000 


160 % 

+ 2,600 % 

F 

Avg. 

62,900 

6,670,000 

694,000 

10 % 

+ 1,100 % 

0/7 

FACULTATIVE ANAEROBES - Plate Count Mean (cfu/ml) 2 

1 

2,300 


240,000 


16,000 

10 

fM 

6.7 % 

+ 700 % 

F 

5 

3,300 

1,100,000 

3,500 

'■'it 

0.3 % 

■ + 6.1 % 

F 

9 

2,000 

430,000 

7,100 

m 

■ ' 

1.7 % 

+360 % 

F 

19 

350,000 4 

1,900,000 

1.500 4 


0.1 % 

- 99 % 

P 

23 

470 

190,000 

12,000,000* 

. 

6,300 % 

+ 2,500,000% 

F 

27 

1,000 

65,000 

2,200 

Piii 

3.4 % 

+ 220 % 

F 

30 

2,100 

290,000 

8,400 


2.9 % 

+ 400 % 

F 

Avg. 

51,600 

602,000 

1,720,000 


+ 290 % 

+ 3,300 % 

1/7 

FECAL COLIFORM (Fecal coliforms/IOOml) 

1 

NG 


NG 


33 

$0 

■ 

NC 

NC 

F 

5 

NG 

NG 

NG 

NC 

NC 

— 

9 

NG 

NG 

NG 

Hi 

NC 

NC 

— 

19 

NG 

NG 

NG 


NC 

NC 

— 

23 

NG 

NG 

NG 


NC 

NC 

— 

27 

NG 

NG 

NG 

m 

NC 

NC 

— 

30 

378 

348 

NG 

s 

8 

0 % 

- 100 % 

P 

Avg. 

54 

50 

5 

m 

10 % 

- 91 % 

1/2 


1 Post-treatment for Event 3 consisted of chlorination, ozonation, UV treatment, a clarifying tank, high efficiency filtration, 
carbon filtration, and polishing filtration. 

2 Plate count mean = average of three separate analyses, reported in colony forming units per milliliter. 

3 A round is considered passing if the final effluent value is < the inlet water value. In the last row, the number of passing values is 
shown in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

4 Anomalous results indicate potential problems with sampling or labeling. No corrective action is required. Data are suspect 
and should be used with extreme caution. 

NG = No growth. NC = Not calculated. 


61 

































































































































criterion for FC was met for one of two rounds for which 
any FC growth occurred; no growth occurred in the inlet 
water, post-BDN, or final effluent for the otherfive tests. No 
FC was detected in the single analysis of the sample 
collected between the ozone and UV oxidation treatment 
units during the 3 rd round of Event 3 (refer to Figure 4-7). 
Thus, no evaluation of UV oxidation effectiveness can be 
made with respect to FC based on these limited data. 

The laboratory results in Table 4-32 indicate that methanol 
was not detected in inlet water samples, but was detected 
in all post BDN and final effluent samples. The mean 
concentration of methanol in post BDN and final effluent 
were both 41 mg/I. The post BDN and final effluent values 
were very similar on a per round basis, indicating that the 
combined ozone and UV oxidation post-treatment had no 
effecton reducing residual methanol concentrations. Thus, 
the secondary criterion of achieving a final effluent with < 
1 mg/I methanol was not met. 

Table 4-33 presents the results of supplemental analyses 
for all outfalls sampled. The majority of the supplemental 
analyses results indicates the BDN and post-treatment 
systems to have little to no effect on the measured 
parameters. As was the case with the previous event, a 
small average concentration of CCI 4 (i.e., 19 pg/l) was 
detected in the inlet water during Event 3. Based on a post 
BDN mean value of 10 pg/l and a final effluent estimated 
mean value of 1pg/l for CCI 4 , the post-treatment system 
(likely the UV oxidation) may have contributed to the 

Table 4-32. Event 3 - Methanol Results (mg/I). 


reduction of that VOC contaminant. 

The increase in TOC following BDN can be attributed to 
the carryover of biological material and/or methanol. The 
increased alkalinity following BDN is consistent with the 
slight increase in pH (refer to Table 4-28). The small 
amounts of phosphate and phosphorus measured in the 
effluent samples is residuum from the 50% methanol 
solution, which contains food grade phosphoric acid. 

4.4.3.5 Mass Removal of Nitrate 

The percentmass removal of nitrate, measured as Nitrate- 
N, was estimated for Event 3 (Objective 4). A total of 
approximately 49,000 gallons, or about 185,000 liters of 
well water was treated during Event 3. Each mg/I of nitrate- 
N is equivalent to 4.4 mg/I of nitrate. Since the mean 
nitrate-N concentration for Event 3 inlet water was 38 mg/I, 
the total mass of nitrate treated during Event 3 final effluent 
was (38 x 4.4) mg/I x 185,000 liters = 31,000,000 mg. The 
mean nitrate-N concentration for Event 3 final effluent was 
8.3 mg/I. The total mass of nitrate in the final effluent = (8.3 
x 4.4) mg/I x 185,000 liters = 6,800,000 mg. Therefore the 
mass removal of nitrate during Event 3 would be 
approximately 31,000,000 mg - 6,800,000 mg = 24,000,000 
mg (a 77% reduction in nitrate). This correlates to 24,000 
grams or 53 pounds. Considering the residual nitrite-N in 
the final effluent, the nitrate-N reduction would decrease to 
51 pounds. 


Sample 
Round No. 

SAMPLE POINT 

Pass/ 

Fail 1 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

1 

< 0.23 

— 

83 

59 

F 

4/5 

< 0.23 

— 

33 

eg 

CO 

F 

9 

< 0.23 

— 

34 

62 

F 

13 

<0.23 

— 

38 

27 

F 

17 

< 0.23 

— 

42 

35 

F 

19 

< 0.23 

— 

31 

34 

F 

23 

< 0.23 

— 

49 

54 

F 

27 

< 0.23 

— 

35 

30 

F 

30 

< 0.23 

— 

26 

33 

F 

Mean 2 

< 0.23 

... 

41 

41 

0/9 


' A round is considered passing if the final effluent value is < 1 mg/I. In the last row, the number of passing values is shown 
in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit considered zero when calculating means. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


62 




















Table 4-33. Event 3 - Supplemental Analyses Results (mg/l).' 


Sample 
Round No. 

Analyte 2 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

4/5,17,27 

CCI 4 

0.019 

— 

0.01 

0.001J 

4/5,17,27 

Total Solids 

582 

... 

459 

467 

4/5,17,27 

Ammonia 

< 0.8 

— 

< 0.8 

< 0.8 

4/5,17,27 

Total Organic 

1.1 

— 

24 

21 

4/5,17,27 

Sulfate 

59 

— 

55 

56 

4/5,17,27 

Phosphate 

< 0.082 

— 

1.4 

1.4 

4/5,17,27 

Alkalinity 

157 

— 

252 

250 


Metals 


4/5,17,27 

Barium 

0.069 


0.068 

0.067 

4/5,17,27 

Calcium 

103 

— 

103 

102 

4/5,17,27 

Potassium 

1.4 

— 

1.2 

1.2 

4/5,17,27 

Magnesium 

28 

_ 

29 

30 

4/5,17,27 

Sodium 

13 

• ... 

15 

16 

4/5,17,27 

Phosphorus 

< 0.37 

... 

1.6 

1.6 


' Values are the mean of the three test results and are rounded to a maximum three significant digits. 

2 Except for CCI 4 only SW-846 8260 contaminants with mean values above detection limits are reported. 

Metals analyzed for included Ag, Al, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Sb, and Zn. 

J = Estimated average value. Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


4.4.3.6 System Performance Vs. Flow Rate 

The performance of EcoMat’s combined BDN and post¬ 
treatment system components were evaluated with respect 
to water flow through the system (Objective 2). The 
variation in inlet water flow rate during Event 3 was 
compared with the total-N concentrations in the final 
effluent. Figure 4-8 directly compares the Event 3 
fluctuation for inlet water flow rate to the Event 3 fluctuation 


in total-N final effluent concentrations on a perround basis. 
The patterns for both plots reflectthe high variability in flow 
rate for Event 3, but still do suggest an inverse correlation 
with system performance. Again, a relationship between 
lowerflow rate and increased BDN effectiveness is evident 
where the somewhat sharp decrease in flow rate occurred 
about one quarter the way through the event, which 
correlates with a reduction in total-N concentration. The 
plots in Figure 4-8 also indicate that the system was never 
really stabilized which in large part was due to system 
perturbations that disrupted Event 3. 


63 































64 









4.4.4 Event 4 

4.4.4.1 Summary 

Event 4 was an 8-day sampling episode conducted 
December 7-14, 1999. During Event 4 a total of 30 
sampling rounds were conducted and ~ 61,000 gallons of 
nitrate-contaminated well water passed through EcoMat’s 
treatment system at an average flow rate of 6 gpm. The 
flow rate among the 30 sampling rounds ranged between 
4.7and 8.3 gpm. Based on an estimated retention capacity 
of 1,300 gallons for the reactor tanks, the sampling rounds 
were conducted ~ 2 to 3Y2 hours apart and from three to 
five times per day. 

Figure 4-9 illustrates the effectiveness of the EcoMat BDN 
and post-treatment systems evaluated during Event 4. The 
mean nitrate-N concentration in PWS Well #1 had 
continued to drop in the six-week period since the Event 3 
testing in October. The mean concentration of nitrate-N in 
the well water during the fourth event was 34 mg/I. During 
the partial BDN in the first reactor (R1), the mean nitrate-N 


levels were reduced by about 44% to 19 mg/I, with a small 
amount of nitrite left over from the nitrate to nitrite 
conversion. Subsequent treatment in the EcoMat reactor 
(R2) further reduced the mean nitrate-N concentration from 
19 mg/I to 8 mg/I. The mean nitrite-N concentration 
increased from 1.3 mg/I to 3.2 mg/I between partial BDN 
and post-BDN samples. A mean total-N concentration of 
approximately 11 mg/I was attained by the BDN treatment 
for Event 4 samples. 

Event 4 post-treatment consisted of chlorination followed 
by clarification, "high efficiency” filtration, air stripping, and 
“polishing” filtration. The post-treatment system had no 
effect on nitrite-N levels; mean nitrate-N concentrations 
were reduced from 3.2 to 0.81 mg/I. The mean total-N 
concentrations for post-BDN and final effluent samples 
were 11.2 mg/I and 11.9 mg/I, respectively. 


60 


c 

o 


40 


c 

o — 
O c 

o £ 
z 

« 
o 


20 


INLET 

WATER 

(from PWS 
Well #1) 


PARTIAL BDN 



Event 4 

Flow @ 6.2 gpm 
Legend 

20 = Total-N concentration (mg/I) 
(19/1) = Nitrate-N / Nitrite-N concentration (mg/I) 

BDN = Biodenitrification 

ND = Not detected > detection limits 


Post 

T reatment 
(See below) 



FINAL 

EFFLUENT 

12 

( 11 / 0 . 8 ) 


0 


Event 4 Post-Treatment Effectiveness 


Post B DN 

MeOH = 27 
TSS = < 5 
Turbidity =1.1 
TCH = 3.5 x 10 8 
FC = > 7 
FA = 1.9 x 10 5 



Final Effluent 



MeOH = 42 
TSS = < 5 
Turbidity = 0.96 
TCH = 4.5 x 10 5 

FP = Q 

FA = 2 x 10 4 


Figure 4-9. Event 4 - Treatment Effectiveness for Averaged Test Results. 


65 





































4.4.4.2 Event 4 Statistical Analysis 

The summary statistics for the critical measurements are 
presented in Table 4-34. Nitrate-N, nitrite-N, and total-N 
results for the four sampling locations for all 30 tests 
comprising Event 4 are shown in Table 4-35. The mean 
values from these data were used in generating Figure 4-9. 


Table 4-34. Event 4 

- Summary Statistics. 

Critical 

Measurement I 

j Mean 
(mg/I) 

Median 

(mg/I) 

Standard 
Deviation (mg/I) 

Post BDN Total-N 1 

J 11.197 

10.550 

5.079 

Final Effluent 
Nitrate-N 

10.63 

11.750 

5.023 

Final Effluent 
Nitrite-N 

0.870 

0.076 

1.523 

Final Effluent 

Total-N 

11.993 

12.076 

5.324 


These data were also used to evaluate the Primary 
Objective (Objective 1). 

The EDA showed that the data from Event 4 closely 
resembled a normal distribution, except for the final effluent 
nitrite-N data which had a large percentage of non-detects. 
When Shapiro-Wilk tests were run, normality was accepted 
forall measurements exceptthe final effluent nitrite-N data. 
Forthesedata neitherthe normal norlognormal distribution 
was shown to fit. Therefore, the non-parametric WSR was 
chosen foranalyzing the final effluent nitrite-N data, butthe 
Student’s t-test was chosen for analyzing the post BDN 
total-N, final effluent nitrate-N, and final effluent total-N. 

Statistical hypothesis tests thatwere conducted yielded the 
following results: 

• Part I: For the Post BDN total-N data, both the 
mean and median were above 10.5 mg/I, so no 
statistical test was needed to determine that the 
Post BDN data did not meet the regulatory limit. 

• Part II: Final Effluent did not meet its performance 
estimate criteria since both the nitrate-N mean and 
median concentrations were > 10.5 mg/I. 

Based on the results of these 2 hypothesis tests, Event 4 
was not shown to be successful in reducing levels of nitrite- 
N and nitrate-N to below regulatory limits. 

4.4.4.3 General Evaluation of BDN System 

Table 4-36 presents the post-BDN and final effluent nitrate- 
N; nitrite-N and total-N results for the four sam pling points 
for each of the 30 Event4 sampling rounds. Also included 


in Table 4-36 are additional analytical data and field 
measurement data that were used for evaluating other 
performance criteria. A total of 11 of the 30 sample rounds 
showed reductions in nitrate-N, nitrite-N, and total-N in the 
final effluent to below the respective regulatory criteria 
(when rounding results to the nearest whole number). 
Other performance results indicated that, on average, the 
Event 4 filtration achieved the best removal of biological 
carryover among all four events, although the levels were 
still well above inlet water levels. The secondary criteria 
results also indicated that the air stripping treatment was 
not effective in reducing residual methanol levels to near 
the desired level of 1 mg/I. 

The daily DO measurements in Table 4-37 show that DO 
in the partial BDN effluent was consistently above 1 mg/I, 
averaged close to 3 mg/I, and was highly variable overthe 
entire event. System disruptions, including unexplainable 
shut-offs of the methanol feed pump, contributed to the 
erratic DO levels. Elevated DO values are an indicatorthat 
anaerobic processes were not optimized and likely 
contributed to the poor performance of Event 4 with respect 
to nitrate-N and nitrite-N removal. 

4.4.4.4 General Evaluation of Post-Treatment System 

The field and laboratory measurements that were used 
primarily for evaluating the post-treatment component of 
EcoMat’s process during Event 4 (Objective 5) included 
pH, turbidity, TSS, microbial analyses, methanol, and 
“supplemental analyses”. 

The daily pH measurements in Table 4-38 indicated a 
continued increase for the inlet water from PWS Well # 1, 
as compared to previous events. However, the pH range 
appears to decrease following BDN treatment. 

Although two final effluent pH values were slightly outside 
of the acceptable drinking water standard range of 6.5 - 
8.5, the pH values for final effluent were improved over inlet 
water values. 

The final effluent turbidity measurements in Table 4-39 
were consistently the lowest of all four events, indicating 
improved post-treatment effectiveness with respect to 
turbidity. Five of seven final effluent measurements, and 
the mean of the seven measurements, were below the 
criterion of 1 NTU. 

Table 4-40 presents the Event 4 laboratory results for TSS. 
As was the case for Event 3, the data show that the inlet 
water and post BDN effluent contain detectable levels of 
TSS in just two of the eight samples. The final effluent data 
indicated that the post-treatment system had a positive 
effect on reducing TSS levels in both of those sample 
rounds, and that the final effluent mean TSS value was 
below the detection limit. One of eight final effluent values 
was higher than the paired inlet water value. Thus, the 


66 
















Table 4-35. Event 4 - Nitrate-N and Nitrite-N Results (mg/I). 


Sample 

Round' 

Nitrate- 

Inlet Water 

Nitrite- 

Total- 

Nitrate- 

Partial BDN 

Nitrite- 

Total- 

Nitrate- 

Post BDN 

Nitrite- 

Total- 

Nitrate- 

Final Effluent 

Nitrite- 

Total- 


N 

N 

N 2 

N 

N 

N 2 

N 

N 

N 2 

N 

N 

N 2 

1 

34.8 

< 0.076 

34.8 

25.4 

0.68 

26.1 

13.9 

4 

17.9 

14.6 

3.8 

18.4 

2 

35 

< 0.076 

35 

27 

0.43 

27.4 

15.5 

3.7 

19.2 

15.8 

3.7 

19.5 

3 

35 

< 0.076 

35 

26.8 

0.39 

27.2 

13 

4.4 

17.4 

19.4 

<0.076 

19.4 

4 

34.8 

< 0.076 

34.8 

25.6 

0.48 

26.1 

12.1 

4.2 

16.3 

16.8 

<0.076 

16.8 

5 

34.6 

< 0.076 

34.6 

27.4 

0.48 

27.9 

14.8 

3.9 

18.7 

18.9 

<0.076 

18.9 

6 

35.3 

< 0.076 

35.3 

26.6 

0.5 

27.1 

14 

3.9 

17.9 

18.6 

<0.076 

18.6 

7 

35.3 

< 0.076 

35.3 

18.3 

1.4 

19.7 

7 

4 

11 

15.3 

<0.076 

15.3 

8 

33.9 

< 0.076 

33.9 

19.8 

1 

20.8 

9.1 

3.1 

12.2 

12 

<0.076 

12 

9 

34.5 

< 0.076 

34.5 

19.1 

0.92 

20.0 

8.4 

3.3 

11.7 

12.8 

<0.076 

12.8 

10 

34 

< 0.076 

34 

21.1 

1.1 

22.2 

9.1 

3.5 

12.6 

13.8 

<0.076 

13.8 

11 

33.5 

< 0.076 

33.5 

17.1 

1.5 

18.6 

4.5 

2.9 

7.4 

8.8 

<0.076 

8.8 

12 

33.5 

< 0.076 

33.5 

20.3 

0.65 

21 

5.6 

3.5 

9.1 

10.6 

<0.076 

10.6 

13 

33.6 

< 0.076 

33.6 

20.7 

1.5 

22.2 

8 

3.4 

11.4 

12 

<0.076 

12 

14 

33.6 

< 0.076 

33.6 

20.6 

1.6 

22.2 

8.3 

3.8 

12.1 

12.1 

0.73 

12.8 

15 

33.2 

< 0.076 

33.2 

21.3 

1.4 

22.7 

14.1 

2.7 

16.8 

17 

<0.076 

17 

16 

34 

< 0.076 

34 

13.5 

2.4 

15.9 

3 

2.5 

5.5 

5.0 

<0.076 

5.0 

17 

33.9 

< 0.076 

33.9 

15.3 

2.5 

17.8 

5.8 

3.1 

8.9 

7.6 

<0.076 

7.6 

18 

33.8 

< 0.076 

33.8 

22.3 

1.3 

23.6 

7 

3.1 

10.1 

9.0 

<0.076 

9.0 

19 

33 

< 0.076 

33 

10.8 

<0.076 

10.8 

2.5 

2.4 

4.9 

5.1 

<0.076 

5.1 

20 

33.9 

< 0.076 

33.9 

17.8 

1.8 

19.6 

5.7 

2.6 

8.3 

9.3 

<0.076 

9.3 

21 

33.1 

< 0.076 

33.1 

29.2 

0.1 

29.3 

6.4 

2.2 

8.6 

12.5 

<0.076 

12.5 

22 

33 

< 0.076 

33 

32.4 

<0.076 

32.4 

16.5 

4.4 

20.9 

16.6 

4.5 

21.1 

23 

33.3 

< 0.076 

33.3 

15 

<0.076 

15 

9.4 

4.4 

13.8 

11.5 

4.6 

16.1 

24 

33 

< 0.076 

33 

15.4 

<0.076 

15.4 

5 

3.3 

8.3 

4.9 

3.6 

8.5 

25 

32.8 

< 0.076 

32.8 

9.4 

<0.076 

9.4 

2.3 

3.4 

4.7 

2.3 

2.4 

4.7 

26 

33.2 

< 0.076 

33.2 

14.5 

<0.076 

14.5 

5.8 

3 

8.8 

7.2 

1.1 

8.3 

27 

33.3 

< 0.076 

33.3 

13.4 

2.3 

15.7 

5.5 

3.3 

8.8 

9.0 

<0.076 

9.0 

28 

32.8 

< 0.076 

32.8 

14 

2.3 

16.3 

4.4 

3 

7.4 

7.6 

<0.076 

7.6 

29 

33.6 

< 0.076 

33.6 

7.9 

1.4 

9.3 

1.4 

1.4 

2.8 

3.3 

<0.076 

3.3 

30 

33.6 

< 0.076 

33.6 

7.9 

1.2 

9.1 

1.3 

1.1 

2.4 

2.5 

<0.076 

2.5 

Mean 3 

34 

< 0.076 

34 

19 

0.98 

20 

8.0 

3.2 

11 

11 

0.81 

12 


1 Represents a sample set in which samples from all four locations were collected at the approximate same time. 

2 Represents combined Nitrate-N and Nitrite-N. Values below the detection limit were considered 0.0 when summing totals. 
5 Means are rounded to two significant digits. Values < detection limit considered zero when calculating means. 


67 







Table 4-36. Event 4 - Summary of Treatment Effectiveness. 



Nitrate-N/Nitrite-N Results (mg/I) 



Post BDN 


Final Effluent 



Sample 

Round 

Total-N’ 

Nitrate-N 

Nitrite-N 

Total-N’ 

Flow 

(flprnJ 

NIp. 

17.9 

14.6 

3.8 

18.4 

' 

2 

19.2 

15.8 

3.7 

19.5 

7.9 

3 

17.4 

19.4 

<0.076 

19.4 

7.9 

4 

16.3 

16.8 

<0.076 

16.8 

6.7 

5 

18.7 

18.9 

<0.076 

18.9 

7.7 

6 

17.9 

18.6 

<0.076 

18.6 

7.7 

7 

11 

15.3 

<0.076 

15.3 

7.5 

8 

12.2 

12 

<0.076 

12 

7.1 

9 

11.7 

12.8 

<0.076 

12.8 

7.9 

10 

12.6 

13.8 

<0.076 

13.8 

8.3 

11 

7.4 

8.8 

<0.076 

8.8 

5.9 

12 

9.1 

10.6 

<0.076 

10.6 

5.5 

13 

11.4 

12 

<0.076 

12 

7.7 

14 

12.1 

12.1 

0.73 

12.8 

7.4 

15 

16.8 

17 

<0.076 

17 

8 

16 

5.5 

5 

<0.076 

5.0 

5 

17 

8.9 

7.6 

<0.076 

7.6 

6.2 

18 

10.1 

9 

<0.076 

9.0 

5.5 

19 

4.9 

5.1 

<0.076 

5.1 

5.2 

20 

8.3 

9.3 

<0.076 

9.3 

6.8 

21 

8.6 

12.5 

<0.076 

12.5 

6 

22 

20.9 

16.6 

4.5 

21.1 

5.3 

23 

13.8 

11.5 

4.6 

16.1 

6 

24 

8.3 

4.9 

3.6 

8.5 

5.9 

25 

4.7 

2.3 

2.4 

4.7 

5.4 

26 

8.8 

7.2 

1.1 

8.3 

6.7 

27 

8.8 

9 

<0.076 

9.0 

6.1 

28 

7.4 

7.6 

<0.076 

7.6 

6.2 

29 

2.8 

3.3 

<0.076 

3.3 

4.7 

30 

2.4 

2.5 

<0.076 

2.5 

4.7 

Mean 3 

11 

11 

0.81 

12 

6.2 


Final Effluent - Other Performance Criteria 


MeOH 

TSS 

Turbidity 

pH 1 2 

Total Heterotrophs 

(mg/i) 

(mg/I) 

(NTU) 

(SU) 

fCFU/mlt 

< 0.23 

< 5 

0.85 

9.0/ 6.8 

22,000/ 1,400,00C 

33 

< 5 

1.3 

9.0/8.4 

... 

— 

— 

— 

... 

34,000 / 8,300 

43 

6 

1.7 

8.7/8.9 

600,000 / 2,000 

38 

< 5 

0.95 

9.2/8.2 

9,800/ 1,200,000 

20 

< 5 

0.77 

9.1 / 8.1 

• 

29 

< 5 

0.77 

9.1 / 8.3 

5,200/ 1,300,000 

43 

< 5 

0.40 

8.3 / 8.6 

480,000 

91 

< 5 

— 

9.0 / 8.2 

5,200/ NG 

37 

< 5 

0.96 

6.8-9.1 

97,000 / 450,00 0 


1 Total-N is equal to the combined Nitrate-N + Nitrite-N concentration. 

2 The first value represents the inlet water and the second value represents the final effluent. 

3 All values, except for the pH range, are means rounded to two significant digits. Values < detection limit considered zero when calculating means. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


68 














Table 4-37. Event 4 - Dissolved Oxygen Measurements (mg/I). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.) 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

12-7-99 

Not Available 

1-5 

9.55 

5.65* 

— 

9.55 

12-8-99 

1200 

6-10 

9.55 

3.70 

4.89 

9.60 

12-9-99 

0915 

11-15 

9.51 

1.50 

— 

9.75 

12-10-99 

Not Available 

16-18 

9.66 

1.87 

3.88 

9.55 

12-11-99 

Not Available 

19-21 

10.32 

2.10 

3.65 

9.58 

12-12-99 

Not Available 

22-24 

9.56 

4.56** 

— 

9.61 

12-13-99 

Not Available 

25-29 

9.70 

1.34 

— 

9.60 

12-14-99 

Not Available 

30 

10.1 

1.28 

— 

9.56 

Mean' 

9.7 

2.8 

4.1 

9.6 


’ Mean values are rounded to two significant digits. 

* Discovered methanol feed pump off. Turned on 1 hour later. 

** Discovered methanol feed pump off. Turned on 2 hours later. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-38. Event 4 - pH Measurements 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.) 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

12-7-99 

Not Available 

1-5 

9.04 

7.48 

— 

6.79 

12-8-99 

Not Available 

6-10 

9.04 

8.59 

8.25 

8.37 

12-9-99 

Not Available 

11-15 

8.65 

8.47 

8.40 

8.93 

12-10-99 

Not Available 

16-18 

9.20 

8.19 

8.13 

8.15 

12-11-99 

Not Available 

19-21 

9.10 

8.32 

8.33 

8.10 

12-12-99 

Not Available 

22-24 

9.05 

8.38 

8.45 

8.27 

12-13-99 

Not Available 

25-29 

8.31 

8.10 

8.88 

8.63 

12-14-99 

Not Available 

30 

9.04 

7.96 

8.30 

8.17 

Range' 

8.3 -9.2 

7.5 -8.6 

8.1 -8.9 

6.8 -8.9 


1 Range values are rounded to two significant digits. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


69 





































Table 4-39. Event 4 - Turbidity Measurements (NTU). 


DATE 

TIME 

INTERVAL 

Associated 
Round No(s.) 

SAMPLE POINT 

Pass/ 
Fail 1 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

12-7-99 

1330 

1-5 

0.05 

... 

... 

0.85 

P 

12-8-99 

1000-1500 

6-10 

0.00 

... 

2.3/1.3 

1.3 

F 

12-9-99 

0815 

11-15 

0.00 

... 

2.2/1.7 

1.7 

F 

12-10-99 

0830 

16-18 

0.03 

... 

1.9/1.0 

0.95 

P 

12-11-99 

0715-1110 

19-21 

0.00 

... 

0.9/1.0 

0.77 

P 

12-12-99 

1445 

22-24 

0.05 

... 

0.9/0.75 

0.77 

P 

12-13-99 

0705 

25-29 

0.00 

— 

1.3/0.9 

0.40 

P 

12-14-99 

0830 

30 

0.05 

... 

... 

— 

... 

Mean 2 

0.02 

— 

1.6/1.1 

0.96 

5/7 


A round is considered passing if the final effluent is < 1 


NTU. In the last row, the number of passing values is shown 


in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 
2 Mean values are rounded to two significant digits. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-40. Event 4 -TSS Results (mg/I). 


Sample 
Round No. 

SAMPLE POINT 

Pass/ 

Fail 1 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

2 

< 5 

... 

< 5 

< 5 

P 

6 

< 5 

... 

< 5 

< 5 

P 

12 

< 5 

... 

12 

6 

F 

17 

< 5 

... 

< 5 

< 5 

P 

20 

< 5 

... 

< 5 

< 5 

P 

23 

< 5 

... 

6 

< 5 

P 

26 

< 5 

... 

<5 

< 5 

P 

30 

< 5 

... 

< 5 

< 5 

P 

Mean 2 

< 5 

... 

< 5 

< 5 

7/8 


1 A round is considered passing if the final effluent value is < the inlet water value. In the last row, the number of passing values is shown 
in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit considered zero when calculating means. 

Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


70 









































secondary drinking water criterion was met for seven of 
eight rounds, which indicated that the filter combination 
used for Event 4 was, for the most part, effective. 

Table 4-41 presents the laboratory results for TCH, FA, 
and FC, at each of the four outfalls. The data indicated the 
TCH population associated with the BDN process was, on 
average, two orders of magnitude higher than TCH levels 
in the well water. On average, approximately 13 percentof 
this bacteria carried over from the BDN process to the final 
effluent. This carryover was similar to that measured for 
Events 2 and 3, which also had filtration incorporated into 
the post-treatment system. However, unlike the previous 
two events, four of the seven final effluent TCH values 
were measured to be below the corresponding inlet water 
values on a per-round basis. Thus, the secondary criteria 
for TCH was met for those tests, but not on an overall 
average basis. 

Like the previous three events, the FA data for Event 4 
followed the expected pattern of greatly increasing in the 
post-BDN effluent and then greatly decreasing in the final 
effluent. The average of the FA plate count mean in the 
inlet water was increased by three orders of magnitude in 
post BDN effluent. The post-treatment was effective in 
reducing the average mean post BDN effluent by one order 
of magnitude. The average mean carryover for the seven 
tests measured was 11 percent and four of the seven final 
effluent mean values were less than the inlet water mean 
value. Thus, the secondary criterion for FA was met for 
those sample rounds, but not met on an overall average 
basis. 

For Event 4, FC was detected in six of the seven inlet 
water samples collected. Of these six samples FC carried 
over to final effluent in only the first sample (although the 
FC in this sample was measured at a concentration above 
that of the inlet water). The secondary criterion for FC was 
met forfive of six sample rounds. Comparable to Event 3, 
results showed that on average, the majority of FC was 
removed during Event 4 post-treatment. 

Table 4-42 presents the Event 4 laboratory results for 
methanol analyses conducted on inlet water, post-BDN 
effluent, and final effluent. Methanol was detected in two 
of eight inlet water samples at low (estimated) 
concentrations. Methanol was also detected in all post 
BDN and final effluent samples (many concentrations were 
estimated values). The mean methanol concentrations in 
post BDN and final effluent were 27 and 42 mg/I, 
respectively. With the exception of sample rounds 12 and 
17, the post BDN and final effluent values were similar on 
a per round basis. This indicates thatthe air stripping post¬ 
treatment did not have a measured effect on reducing 
residual methanol concentrations, except possibly for 
round 2, where an estimated 1mg/l of methanol in post 
BDN effluent was not detected in the paired final effluent 
sample. Thus, the secondary criteria of achieving a final 


effluent with < 1 mg/I methanol was not met as a mean, 
nor for 7 of the 8 sampling rounds. 

Table 4-43 presents the results of supplemental analyses 
for all outfalls sampled. Most of the results of these 
supplemental analyses indicate that the BDN and post¬ 
treatment systems had little to no effect on the measured 
parameters. The only VOC detected in the inlet water was 
a small amount of CCI 4 . Since CCI 4 was not detected in 
either the post BDN or final effluents, it is likely that the 
0.007 mg/I of that compound was volatilized or degraded 
during the BDN process. 

The increase in TOC following BDN can be attributed to 
carryover of biological material and/or methanol. The 
subsequent drop in TOC in final effluent may be an 
indication of a positive post-treatment impact (e.g., 
filtration). The increased alkalinity following BDN, unlike the 
other three events, does not correlate with the slight 
decrease in pH measurements recorded for the final 
effluent (refer to Table 4-38). The small amounts of 
phosphate and phosphorus measured in the effluent 
samples is residuum from the 50% methanol solution, 
which contains food grade phosphoric acid. 

4.4.4.5 Mass Removal of Nitrate 

The percent mass removal of nitrate, measured as Nitrate- 
N, was estimated for Event 4 (Objective 4). A total of ~ 
61,000 gallons (-230,000 liters) of well water was treated 
during Event 4. Each mg/I of nitrate-N is equivalent to 4.4 
mg/I of nitrate. Since the mean nitrate-N concentration for 
Event 4 inlet water was about 34 mg/I, the total mass of 
nitrate treated during Event 4 was (34 x 4.4) mg/I x 230,000 
liters = 34,000,000 mg. The mean nitrate-N concentration 
for Event 4 final effluent was 11.4 mg/I. The total mass of 
nitrate in the Event 4 final effluent = (11 x 4.4) mg/I x 
230,000 liters = 1 1,000,000 mg. Therefore, the mass 
removal of nitrate would be about 34,000,000 mg - 
11,000,000 mg = 23,000,000 mg (a 68% reduction in 
nitrate). This correlates to 23,000 grams or 51 pounds. 

4.4.4.6 System Performance Vs. Flow Rate 

The performance of EcoMat’s combined BDN and post¬ 
treatment system components were evaluated with respect 
to water flow through the system (Objective 2). The 
variation in inlet water flow rate during Event 4 was 
compared with the total-N concentrations in the final 
effluent. Figure 4-10 directly compares the Event 4 
fluctuation for inlet water flow rate to the Event 4 fluctuation 
in total-N final effluent concentrations on a perround basis. 
As was the case with third event, Event 4 was typified by 
rather high variability in flow rate and system performance. 
The pattern for both of the plots reflects a very close 
relationship between flow rate and system performance. 
There is also an obvious trend of steady flow rate reduction 
coupled with a steady BDN improvement from start to 


71 




Table 4-41. Event 4 - Microbial Results. 1 


Sample 

Round 

No. 

TOTAL CULTURABLE HETEROTROPHS - Plate Count Mean (cfu/ml) 2 

Inlet 
Water 2 


Post 

BDN 2 


Final 

Effluent 2 

% Carryover 
from BDN 

% Change from 
Inlet Water 

Pass / 
Fail 3 

2 

21,500 

7,500,000 

1,370,000 

18 % 

+ 6,400 % 

F 

8 

33,500 

5,800,000 

8,300 

0.14 % 

- 75 % 

P 

12 

600,000 

3,800,000 

2,000 

0.05 % 

- > 99 % 

P 

17 

9,800 

1,950,000 

670 

0.03 % 

- 93 % 

P 

23 

5,200 

1,970,000 

1,300,000 

66 % 

+ 25,000 % 

F 

26 

4,000 

1,800,000 

480,000 

27 % 

+ 12,000 % 

F 

30 

5,200 

1,700,000 

0 

0 % 

- 100 % 

P 

Avg. 

97,000 

3,500,000 

450,000 

13 % 

+ 460 % 

4/7 

FACULTATIVE ANAEROBES - Plate Count Mean (cfu/ml) 2 

2 

180 


88,000 


9,200 

10 % 

+ 5,100 % 

F 

8 

190 

90,000 

58 

0.06 % 

- 70 % 

P 

12 

260 

440,000 

28 

0.01 % 

- 89 % 

P 

17 

180 

130,000 

6 

0.01 % 

- 97 % 

P 

23 

1,200 

380,000 

130,000 

34 % 

+ 11,000 % 

F 

26 

440 

120,000 

440 

0.4 % 

0.0 % 

P 

30 

340 

80,000 

2,400 

3 % 

+ 700 % 

F 

Avg. 

400 

190,000 

20,300 

11 % 

+ 5,100 % 

4/7 

FECAL COLIFORM (Fecal coliforms/IOOml) 

2 

40 


48 


62 

130% 

1.6 

F 

8 

94 

TNC 

NG 

0 % 

- 100 % 

P 

12 

158 

NG 

NG 

0 % 

- 100 % 

P 

17 

210 

NG 

NG 

0 % 

- 100 % 

P 

23 

38 

NG 

NG 

0 % 

- 100 % 

P 

26 

55 

NG 

NG 

0 % 

- 100 % 

P 

30 

NG 

NG 

NG 

NC 

NC 

— 

Avg. 

85 

>7 

9 

NC 

- 89 % 

5/6 


1 Post-treatment for Event 4 consisted of chlorination, clarification, high efficiency filtration, air stripping, and polishing filtration. 

2 Plate count mean = average of three separate analyses, reported in colony forming units per milliliter. 

3 A result is considered passing if the final effluent value is < the inlet water value. 

NG = No growth. NC = Not calculated. TNC = Too Numerous to Count. 


72 
































































































































Table 4-42. Event 4 - Methanol Results (mg/I). 


Sample 
Round No. 

SAMPLE POINT 

Pass/ 

Fail ’ 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

2 

2.8 J, 

— 

1 J 

<0.23 

P 

6 

< 0.23 

— 

14 

33 

F 

12 

< 0.23 

— 

4.1 J, 

43 J 2 

t 

F 

17 

< 0.23 

— 

5.1 J 2 

38 

F 

20 

< 0.23 

— 

37 J 2 

55 J 2 

F 

23 

< 0.23 

— 

32 J 2 

29 J 2 

F 

26 

< 0.23 

— 

43 J 2 

43 

F 

30 

0.3 J, 

— 

79 J 2 

91 

F 

Mean 2 

0.4 J 

— 

27 

42 

1/8 


1 A round is considered passing if the final effluent value is < 1 mg/I. In the last row, the number of passing values is shown 


in the numerator; the total number of values (pass + fail, minus any blank values) is shown in the denominator. 

2 Mean values are rounded to two significant digits. Values < detection limit considered zero when calculating means. 
J, These values should be considered estimates due to the uncertainty in the low end of the curve. 

J 2 These values should be considered estimates due to the possibility of peak interferences from a second peak. 
Dashed line indicates that samples collected at that location were not analyzed for that parameter. 


Table 4-43. Event 4 - Supplemental Analyses Results (mg/I).’ 


Sample Round 
Nos. 

Analyte 2 

SAMPLE POINT 

Inlet Water 

Partial BDN 

Post BDN 

Final Effluent 

6, 17, 27 

CCI 4 

0.007 

— 

< 0.005 

< 0.003 

6, 17, 27 

Total Solids 

365 

— 

437 

495 

6, 17, 27 

Ammonia 

< 0.8 

— 

<0.8 

< 0.8 

6, 17, 27 

Total Organic Carbon 

< 1 

— 

49.8 

16.2 

6, 17, 27 

Sulfate 

54.8 

— 

54.8 

54.7 

6, 17, 27 

Phosphate 

< 0.082 

— 

1.4 

0.84* 

6, 17, 27 

Alkalinity 

147 

— 

225 

229 


Metals 



6, 17, 27 

Barium 

0.061 

— 

0.055 

0.052 

6, 17, 27 

Calcium 

82 

— 

91 

87 

6, 17, 27 

• 

Potassium 

1.1 

— 

1.21.1 

6, 17, 27 

Magnesium 

23 

— 

25 

25 

6, 17, 27 

Sodium 

13 

— 

15 

33 

6,17, 27 

Phosphorus 

< 0.37 

— 

1.5 

1.5 


1 Values are the mean of the three test results and are rounded to a maximum three significant digits. 

2 Except for CCI 4 only SW-846 Method contaminants with mean values above detection limits are reported. 
Metals analyzed for included Ag, Al, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Sb, and Zn. 


73 















































Figure 4-10. Event 4 - Comparison of Flow Rate Fluctuation and Final Effluent Total-N Concentration 


finish. The only exception to this pattern is an abrupt sharp 
increase in the total-N levels about 3/4 of the way through 
the event. This anomalous peak is believed to be the result 
of an inadvertent shut off of the methanol feed pump that 
disrupted the treatment system. 

4.4.5 Inter-Event Comparison 

This section evaluates the overall demonstration 
performance of the EcoMat BDN treatment system with 
respect to nitrate-N, nitrite-N, total-N and several key field 
and analytical parameters. Direct comparisons are made 
among the four events in order to investigate possible 
reasons for variable performance. 

4.4.5.1 BDN Performance 

Figure 4-11 shows the mean total-N concentrations for 
each individual event plotted against one another. The 
mean nitrate-N and nitrite-N concentrations for all tests 
conducted during a particular event are presented as data 
pairs in boxes. Several observations can be made from this 
figure. First, forallfourevents, the concentration of nitrate- 
N in the untreated inlet water from PWS Well # 1 was well 
in excess of both the 10 mg/I MCL and the 20 mg/I 


threshold set for the demonstration. The inlet water nitrate- 
N concentrations were considerably higher for Events 1 
and 2, as compared to Events 3 and 4. Based on daily 
water level measurements taken during all four events, 
there was a significantwaterleveldropof approximately 14 
feet in PWS Well # 1 between Events 2 and 3. Thus, there 
may have been a corresponding drop in the amount of 
nitrate being flushed into the well during the dryer months 
preceding Events 3 and 4. 

Figure 4-11 also illustrates that, during the initial stages of 
BDN, the nitrate-N concentrations were reduced by similar 
percentages for all four events (i.e., 52-60%), while at the 
same time small amounts of nitrite-N were being generated 
from the reduction of nitrate. Following BDN, the mean 
nitrate-N concentrations were further reduced to below 10 
mg/I, and mean nitrite-N concentrations increased forthree 
of the four events. Following post-treatment the mean 
nitrite-N concentrations were reduced forallevents, except 
for Event 2, where the mean nitrite-N level remained 
essentially the same. As expected, there was no 
appreciable difference in the mean final effluent nitrate-N 
concentration, following post-treatment. 


74 










4.4.5.2 Final Effluent Water Quality 

Table 4-44 summarizes relevant criteria-oriented final 
effluent data collected during the demonstration as 
averages for all four events. Except for the relevant 
process parameters, all values represent final effluent 
means. The mean DO levels for water exiting the 
deoxygenating tank have been included due to the 
importance of that field measurement in determining proper 
anoxic conditions. In genera I terms, the final effluent mean 
nitrate-N concentrations increased when the DO was not 
maintained near the desired 1 mg/I level. 

The increased post-treatment following the first event had 
less impact than anticipated (e.g., neither the carbon 
filtration employed during Event 3 nor the air stripping 
employed during Event 4 appears to have had a significant 
impact on methanol levels in the final effluent). Although 


TSS and turbidity improved to or near acceptable 
concentrations when filtration was employed, carryover of 
biological material from the EcoMat reactor to the final 
effluent remained considerable. 

None of the oxidation post-treatments (chlorination, UV 
oxidation, or ozone) appeared to have any beneficial 
effects on residual bacterial matter, methanol destruction, 
or re-oxidation of nitrite to nitrate. It is not known whether 
this was due to inappropriate sizing, variability in feed rate 
or other, unknown factors. There also was some question 
whether ongoing biodegradation was occurring in some 
sample containers between collection and analysis. This 
could have taken place in BDN samples, resulting in lower 
methanol results before post-treatment, but would have 
been inhibited in oxidized samples. The overall EcoMat 
process appears to have little impact on pH. 


75 














































Table 4-44 Inter-Event Comparison of Demonstration Criteria for Final Effluent.' 


Parameter 

Criterion 

SAMPLING EVENT 

Event 1 

(May 6-15) 

Event 2 

(August 3-12) 

Event 3 

(October 20-28) 

Event 4 

(December 7-14) 

Process Parameters 

Flow (qpm) 

3-15 

3.0 

3.5 

4.2 

6.2 

Total Gallons Treated 


42,000 

45,000 

49,000 

61.000 

DO in Partial BDN Effluent (mq/l) 


1.1 

1.0 

2.1 

2.8 

Biodenitrification Parameters 

Nitrate-N (mg/I) 

< 10 

1.7 J 

4.1 

8.3 

11 

Nitrite-N (mg/I) 

< 1 

0.4 

1.5 

1.5 

0.8 

Total-N (mg/I) 2 

< 10 

r: 

2.1 

5.6 

9.9 

12 

Post-Treatment Parameters 

Post-Treatment System 


► Chlorination 

► Clarification 

► Sand Filtration 

► Rough Filtration 
► UV Oxidation 

► Ozone 
► UV Oxidation 
►Clarification 
► Rough Filtration 

► High Eff. Filtration 

► Carbon Filtration 
► Polishing Filtration 

► Chlorination 

► Clarification 

► High Eff. Filtration 

► Air Stripping 

► Polishing Filtration 

Residual Methanol (mg/I) 

< 1 mg/I 

15 

98 

41 

37 

Turbidity (NTU) 

< 1 NTU 

4.4 

1.8 

1.2 

0.96 

Total Suspended Solids 3 

5 inlet water 

<5 / 10 

<5 / < 5 

■ 

<5/< 5 

----— - - 

<5/<5 : C;:; 

pH Range (min-max) 

6.5 -8.5 

7.5 -8.6 

7.6 -8.4 

7.9-8.2 

6.8 -8.9 

Total Heterotrophs (% change) 

< inlet water 

+ 19,000 

+ 18,000 

+ 1,100 

+ 460 

Fac. Anaerobes (% change) 

< inlet water 

+ 7,300 

+ 170,000 

+ 3,300 

+ 5,100 

Fecal Conform (% change) 

< inlet water 

NC 

-75 

' 91 

- 89 


' Values are means that have been rounded to a maximum two significant digits. Bolded values meet criteria; shaded boxes denote best result of 
the four events. 

2 Total-N is equal to the combined Nitrate-N + Nitrite-N. 


4.4.6 Data Quality Assurance 

This section of the ITER contains a review of the critical 
sample data and associated QC analyses that were 
performed to determine whether the data collected were of 
adequate quality to provide proper evaluation of the 
project’s technical objectives. A more detailed summary 
and discussion of quality assurance/quality control 
information regarding the EcoMat SITE demonstration is 
included in the TER. The results of the critical 
measurements designed to assess the data quality 
objectives are summarized in the following subsections. 

4.4.6.1 Accuracy 

Accuracy objectives for nitrate-N and nitrite-N were 
assessed by the evaluation of 46 spiked duplicates 


analyzed in the same manner as the samples. Recovery 
values for the critical compounds were well within project 
objectives, with two exceptions. Two of the samples 
contained sufficient chemical (intentionally introduced into 
the EcoMat treatment stream for this same purpose) to 
convert the nitrite spike added to nitrate. The chemicals 
added, or treatments, were done to convert the nitrite to 
nitrate and assist in meeting the 1 ppm concentration limit 
for nitrite. The following adjustments were done; 

Event 1-Chlorination-calcium hypochlorite- 
pool filter chlorine tablets 
Event 2 - UV oxidation 
Event 3 - Ozone and UV oxidation 
Event 4 - Chlorine liquid 


76 


















































Oxidation of the nitrite to nitrate likely continued after 
sample collection. This oxidation reaction is part of the 
treatment process. Any residual nitrite in the samples 
would be considered more hazardous in terms of health 
effects and therefore the oxidation reaction which is 
considered beneficial, would convert residual nitrite to 
nitrate, with total nitrate levels still expected to be below 10 
ppm. Chemicals added in the final stage of treatment were 
specifically designed for this purpose. This explains poor 
recoveries of some of the matrix spikes for nitrite. 
Therefore, this is not believed to be an analytical problem. 

It is likely that residual chemicals (e.g., chlorine and ozone) 
continued to react with samples after spike addition and 
prior to analysis. Low recoveries for matrix spikes in these 
samples should therefore be treated as a “matrix problem" 
due to a continued oxidation reaction. LCS results are 
therefore considered as the “analytical indicator" showing 
reasonable recovery of nitrite for these particular sample 
batches. The preceding text explains the rationale for 
addition of oxidizing agents. 

The two spike recovery values (one from each of the 
chemically treated Events 1 and 4) are not included in the 
statistical evaluation of the spikes; therefore, a total of 44 
of the 46 matrix spike/matrix spike duplicate (MS/MSD) 
sample sets are used in the statistical evaluation. 
Recovery fornitrate-N averaged 95.4% and for nitrite-N the 
average recovery was 95.8% (Tables 4-45 and 4-46). 

4.4.6.2 Precision 

Precision was assessed through the analysis of 44 
duplicate spikes. Again, 46 MS/MSD were performed by 
the laboratory; however, due to the conversion of nitrite to 
nitrate by the sample only 44 are statistically evaluated. 
Data quality objectives forprecision, established as relative 
percent difference (RPD) values less than 15%, were met 
with one exception. Nitrate-as-nitrogen RPDs averaged 
2.7% and nitrite-as-nitrogen RPD values averaged 2.1% 
(Tables 4-47 and 4-48). 


4.4.6.3 Detection Limits 

Detection limits were established so as to be sufficiently 
below the concentration of interest (established by 
regulatory limits) for nitrite and nitrate. Nitrite had a 
detection limit of 0.076 mg/I with a concentration of interest 
(decision point) of 1 mg/I. Nitrate had a detection limit of 
0.056 mg/I with a concentration of interest (decision point) 
of 10 mg/I. The concentration of interest for methanol was 
established by the project since there is no regulatory level 
formethanolin drinking water. The methanol concentration 
of interest was established as 1.0 mg/I with a detection limit 
of 0.23 mg/I. 

4.4.6.4 Comparability 

Comparability was achieved through the use of QAPP 
approved EPA protocols and verified by the validation of 
analytical data, which indicated that QAPP and method- 
specified criteria were met. 

4.4.6.5 Completeness 

Sufficient samples were collected to satisfy statistical 
completeness requirements. A minimum of 28 sample sets 
were collected for each event for evaluating nitrate and 
nitrite treatment effectiveness. 

4.4.6.6 Representativeness 

Representativeness refers to the degree with which a 
sample exhibits average properties of the waste stream at 
the particular time being evaluated. This is assessed in 
part by the analysis of field duplicates, which also provide 
insight into the homogeneity, or heterogeneity, of the 
matrix. Field duplicate samples have, inherent in the result, 
combined field and analytical variability. For this project, 
the primary sample and duplicate sample were collected 
immediately after each other. These indicated reasonable 
agreement in results, with RPD values for field duplicates 
from all four events generally less than 25%. The average 
RPD for nitrate was 10.9% and for nitrite 4.3% (Tables 4- 
49 and 4-50). 


77 





Table 4-45. Nitrate Matrix Spike Percent Recovery Summary. 


Event 

Recovery Range 

Number of Duplicate Pairs 

Percent Recovery Average 

Event 1 (May 99) 

87.8% to 103.1% 

n=14 

95.3% 

Event 2 (August 99) 

86.9% to 105.4% 

n=10 

93.7% 

Event 3 (November 99) 

86.8% to 107.6% 

n=12 

96.8% 

Event 4 (December 99) 

89.4% to 108.1% 

n=8 

95.7% 

Overall Demonstration 

86.8% to 107.6% 

n=44 

_95_ 


Table 4-46. Nitrite Matrix Spike Percent Recovery Summary. 


Event 

Recovery Range 

Number of Duplicate Pairs 

Percent Recovery Average 

Event 1 (May 99) 

83.1% to 104.8% 

n=14 

90.8% 

Event 2 (August 99) 

92.0% to 103.4% 

n=10 

96.5% 

Event 3 (November 99) 

91.6% to 107.1% 

n=12 

99.0% 

Event 4 (December 99) 

95.6% to 107.8% 

n=8 

98.7% 

Overall Demonstration 

_83.1% to 107.8%_ 

n=44 

_ 2Z3& _ 


Table 4-47. Nitrate MS/MSD Relative Percent Difference Summary. 


Event 

MS/MSD RPD Range 

Number of Duplicate Pairs 

Average MS/MSD RPD 

Event 1 (May 99) 

0.0% to 9.7% 

n=14 

2.6% 

Event 2 (August 99) 

1.4% to 4.9% 

n=10 

2.9% 

Event 3 (November 99) 

0.0% to 24.2% 

n=12 

3.6% 

Event 4 (December 99) 

0.2% to 3.8% 

n=8 

1.5% 

Overall Demonstration 

0.0% to 24.2% 

n=44 

2.7% 


Table 4-48. Nitrite MS/MSD Relative Percent Difference Summary. 


Event 

MS/MSD RPD Range 

Number of Duplicate Pairs 

Average MS/MSD RPD 

Event 1 (May 99) 

0.4% to 7.1% 

n=14 

2.1% 

Event 2 (August 99) 

0.3% to 5.9% 

n=10 

1.4% 

Event 3 (November 99) 

0.0% to 6.5% 

n=12 

2.1% 

Event 4 (December 99) 

0.0% to 8.3% 

n=8 

3.1% 

Overall Demonstration 

0.0% to 8.3% 

n=44 

2.1% 


78 








































Table 4-49. Nitrate Field Duplicate Summary. 


Event 

RPD Range 

Number of Field Duplicates 

Average RPD 

Event 1 (May 99) 

0.0% to 108% 

n=7 

31.9% 

Event 2 (August 99) 

0.0% to 4.7% 

n=6 

0.8% 

Event 3 (November 99) 

0.0% to 3.2% 

n=5 

1.5% 

Event 4 (December 99) 

0.0% to 23.9% 

n=7 

5.4% 

Overall Demonstration 

0.0% to 108% 

n=25 

10.9% 


Table 4-50. Nitrite Field Duplicate Summary. 


Event 

RPD Range 

Number of Field Duplicates 

Average RPD 

Event 1 (May 99) 

3.4% to 16.0% 

n=7 

7.7% 

Event 2 (August 99) 

0.0% to 3.5% 

n=5 

1.0% 

Event 3 (November 99) 

0.0% to 5.8% 

n=4 

3.5% 

Event 4 (December 99) 

0.0% to 5.9% 

n=4 

3.4% 

Overall Demonstration 

0.0% to 16.0% 

n=20 

4.3% 


79 





















Section 5.0 

Other Technology Requirements 


5.1 Environmental Regulation 
Requirements 

State and local regulatory agencies may require permits 
prior to implementing a BDN technology. Most federal 
permits will be issued by the authorized state agency. An 
air permit issued by the state Air Quality Control Region 
may be required if an air stripper is utilized as part of the 
post-treatment system (i.e., if the air emissions are of toxic 
concern or anticipated to be in excess of regulatory 
criteria). Wastewater discharge permits may be required if 
any such wastewater were to be discharged to a POTW. 
If remediation is conducted at a Superfund site, federal 
agencies, primarily the U.S. EPA, will provide regulatory 
oversight. If off-site disposal of contaminated waste is 
required, the waste must be taken to the disposal facility by 
a licensed transporter. Section 2 of this report discusses 
the environmental regulations that may apply to the EcoMat 
Inc. BDN treatment process. 

5.2 Personnel Issues 

The number of personnel required to operate the EcoMat 
Biodenitrification technology should be small and is not 
critically dependent on the size of the treatment system. 
Large systems may, however, require extensive site 
preparation and assembly operations that may require 
several individuals (inclusive of contractors), especially if 
there are constraints on time. For smaller treatment 
systems, requiring minimal site preparation, as few as one 
person may be needed to assemble and conduct the initial 
startup testing of the system. 

During the demonstration EcoMat, in most instances, had 
one company employee at the pilot unit. They also had 
one local person to periodically monitor the system and 
collect samples in their absence. Estimated labor 
requirements for a full-scale 100 gpm system are 
discussed in detail in Section 3 of this report. 


During the demonstration sampling events, two SITE team 
members were required to conduct field measurements 
and to collect and prepare samples. Personnel present 
during sample collection activities at a hazardous waste 
site must have current OSHA health and safety 
certification. Although the BDN technology targets nitrate 
and other inorganic contaminants, gas detection tubes 
should be used to monitor the air in the vicinity of the 
treatment system to monitor for sulfide, chlorine, ozone, 
and other potential gases. Respiratory protective 
equipment may be needed in rare instances, but are not 
anticipated. 

At sites with greater complexity and risk, the personnel 
protective equipment (PPE) for workers will include steel¬ 
toed shoes or boots, safety glasses, hard hats, and 
chemical resistant gloves. Depending on contaminant 
types, additional PPE (such as respirators) may be 
required. Noise levels would usually not be a concern. 
However, loud pumps for larger systems could create 
appreciable noise. Thus, noise levels should be monitored 
to ensure that workers are not exposed to noise levels 
above the time weighted average of 85 decibels over an 8- 
hour day. If this level is exceeded and cannot be reduced, 
workers would be required to wear hearing protection. 

5.3 Community Acceptance 

Potential hazards to a surrounding community may include 
exposure to air emissions of VOCs, if those contaminants 
are also present in the water stream (along with the 
nitrates). Ozone and chlorine emissions are also possible 
if such post-treatment is incorporated. 

Overall, there are few environmental disturbances 
associated with the BDN processes. No appreciable noise 
is anticipated beyond that generated by the short term use 
of power washing equipment (used during general 
maintenance), or by excessively loud pumps. Since most 
units are contained in a secured building, disturbances 
from the system are kept within the building confines. 


80 



Section 6.0 
Technology Status 


6.1 Previous Experience 

The pilot-scale treatment system that was set up at the 
Bendena, Kansas site was EcoMat’s first application of 
their BDN technology for treatment of contaminated 
groundwater. Priorto this project, EcoMat has applied their 
technology to the commercial aquarium industry where 
health of the fish is a prime economic concern. EcoMat is 
presently the only company to provide the denitrification 
technology for the aquarium industry. EcoMat's systems 
are applied at the following aquariums. 

• The John G. Shedd Aquarium (Chicago) 

• The Albuquerque Biological Park Aquarium 

• Biodome de Montreal 

• New Jersey State Aquarium 

• Sea World of Florida 

• Large Aquarium System 

• Colorado’s Ocean Journey (Denver) 

Based on their experience gained during the SITE 

Demonstration in Bendena, EcoMat has improved 
dissolved oxygen monitoring by inserting a dissolved 
oxygen meter into their system. 

Currently, EcoMat has installed a small reactor to remove 


perchlorate from a Department of Defense facility in 
Southern California (see Appendix A). To treat perchlorate, 
the process operates on the same principle as for nitrate 
treatment. In the absence of both dissolved oxygen and 
nitrate, the bacteria take oxygen from perchlorate and yield 
a simple chloride ion. 

In-house research is being conducted forthe nitrification of 
ammonia. EcoMat has slightly modified their pilot-scale 
reactor to permit the addition of large amounts of air into 
the reactor. The bacteria used for nitrification are very 
different from denitrification bacteria, in that they are highly 
sensitive to a number of parameters. EcoMat uses an on¬ 
line fermentation process to continually produce them. 

6.2 Ability to Scale Up 

EcoMat has sold systems treating less than one gpm to 
aquariums and has supplied reactors as large as three 
cubic meters. They currently have a single reactor design 
that would treat influent at a flow rate of 200 gpm. EcoMat 
has also indicated that there is no upper limit to capacity to 
their technology. For very large systems multiple reactors 
would be used. 


81 




Section 7.0 
References 


EcoMat Inc. Internet Web Site, www.ecomatinc.com 

Evergreen Analytical Laboratory. June 3,1999; September 
5, 1999; November 23, 1999; January 5, 2000; Analytical 
Results (Data Packages) for samples submitted for SAIC 
Project - EcoMat Inc.’s Biological Denitrification and 
Removal of Carbon Tetrachloride. 

Hall, P.J. August, 2000. Perchlorate Remediation ata DOD 
Facility (not published). 

Microbac Laboratories, Inc. - Bio Renewal Division. May 27, 
1999; September 1,1999; November 16, 1999; December 
28, 1999. Results from Anaerobic Plate Count Analyses in 
Connection with the EcoMat site located in Bendena, KS. 


Microbial Insights, Inc. May 3, 1999. Microbial 

Characterization for EcoMat Inc.’s Biological Denitrification 
Process: Analysis of Water Samples by PLFA, Total 
Culturable Heterotrophs, and Fecal Conforms. 

SAIC. April 1999. Quality Assurance Project Plan for 
EcoMat Inc.’s Biological Denitrification and Removal of 
Carbon Tetrachloride at the Bendena site, Doniphan 
County, Kansas. 

Shapiro, J.L., P. Hall, and R. Bean. January 2000. Ground 
Water Denitrification at a Kansas Well. Presented at the 
Technology Expo and International Symposium on Small 
Drinking Water and Wastewater Systems, Phoenix, 
Arizona. 


82 



Appendix A 


Developer Claims and Discussion 






































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Note: Information contained in this appendix was 
provided by EcoMat, Inc. and has not been 
independently verified by the U.S. EPA SITE Program 

A.1 Case Study - Perchlorate Remediation 
at a DOD Facility 

The site is a Department of Defense facility located in 
Southern California. Under the Installation Restoration 
Program (IRP), Earth Tech, Inc. has a contract to provide 
environmental services, including evaluating the 
perchlorate levels in shallow groundwater underthe facility. 
The test water that they pump from this activity is 
temporarily stored in Baker tanks on the site. The major 
contaminant in this water is perchlorate, at concentrations 
varying from 300 ppb to 1000 ppb. Beginning in October 
1999 Earth Tech evaluated EcoMat’s ability to remediate 
perchlorate and in December 1999 they contracted with 
EcoMatto provide a small system forremoving perchlorate 
from the test water. 

A.1.1 Project Activity 

EcoMat designed a system to achieve the removal of 
perchlorate from the Bakertanks within a period of several 
months. At the beginning there was not sufficient 
information to determine the hydraulic residence time for 
removal of perchlorate down to non-detectable levels, so 
the system was designed for a residence time of 
approximately one-half hour with an active volume of 200 
liters. Given average tank volumes of 20,000 gallons this 
would enable complete reduction in a period of seven days 
after the bacteria are firmly established. 

EcoMat had designed and built an identical system and 
installed it in the John G. Shedd Aquarium in Chicago. The 
design is described in the following section. It was built on 
a single skid in our Hayward facility. Denitrification bacteria 
which had been exposed to perchlorate were placed in the 
reactors and then the entire skid was loaded onto a panel 
truck and driven down to Southern California. At the site, 
it was lifted off the truck and placed in a temporary shelter 
near the Baker tanks, and started up. Within a few days it 
was functioning and reducing perchlorate. After the first 
few days the system’s operation was transferred to Earth 
Tech, with telephone contact and advice from EcoMat. 

After several months during which various operating 
problems were dealt with, the tanks were completely clean 
of perchlorate, below the detectable concentration. The 
system was then moved to a similar site on the base, 
where it remains in operation. 

A.1.2 System Design 

The system is best described using a flow diagram (see 
Figure A-1 ). Water is drawn from the Baker tank into the 
top of the deaeration reactor. This reflects a basic 


understanding by EcoMat that a two-stage process works 
best for biological oxygen removal. In the deaeration tank 
there is a large number of ordinary bio-balls that provide 
surface for bacterial growth. The reactor is designed to 
reduce the dissolved oxygen concentration from saturation 
down to a concentration of 0.5-1.0 ppm. This is the 
optimum concentration for either denitrification or 
perchlorate remediation. If the dissolved oxygen 
concentration rises above one ppm, the remediation is 
ineffective, and if itdrops to near-anaerobic concentrations, 
the threat of sulfate attack arises. Hydrogen sulfide can be 
injurious to the bacteria, stopping the remediation activity. 
Although the bacteria can be revived very easily by 
restarting the process, time is wasted if oxygen levels are 
not monitored. 

From the bottom of the deaeration reactor, water is then 
drawn into the bottom of the Hall reactor. This patented 
reactor is the key element of EcoMat’s process. It is 
designed to hold a mass of floating media and maintain 
continuous circulation of the media along with the water in 
the reactor. This mixing is attained without any internal 
moving parts, but rather, by external pump re-circulation 
(as shown in Figure 4-2 of the ITER). Continuous 
circulation is extremely important as it provides for uniform, 
low concentrations of the contaminant under ALL influent 
contaminant concentrations. This factor is key to EcoMat’s 
success in both denitrification as well as perchlorate 
remediation as it puts no upper limit on the allowable inlet 
concentrations. 

At this point we must say more about the EcoLink media 
(see ITER cover). This is a polyurethane-based sponge 
that is cut into one-centimeter cubes. The media last for a 
very long time— up to several years. They are kept 
reasonably clean and capable of supporting bacteria 
colonies by virtue of their gentle collisions with each other 
and with the walls of the reactor. When functioning to 
produce a gas, as in denitrification, the size of the 
interstitial spaces within the sponge is designed to permit 
passage of gas out, as well as passage of water into, these 
spaces. At the same time, the surface area involved is 
sufficiently great to provide for large bacteria 
concentrations and high interaction efficiency. 

The overflow from the Hall reactor is recycled back into the 
deaeration reactor during the startup period to form 
colonies of bacteria. In normal operation the effluent is 
discharged from the system. In cases where drinking 
water purity is desired, a post-treatment system can be 
added to the process to control the small amount of 
biosolids that leaves the system. This is the only residual 
stream that results from the process. In case of upset 
conditions, water can be returned to the Baker tanks. 

Both reactors require feed of a carbon source (electron 
donor) to feed the bacteria. EcoMat has studied a variety 
of available sources and we find that the best one is 
methanol. Methanol residual of less than 2 ppm is 


A-1 



Figure A-1. EcoMat Perchlorate Removal System. 


considered non-hazardous and EcoMat’s systems normally 
run at undetectable concentrations (below 0.5 ppm). 
Methanol is not only the lowest cost commercially available 
carbon source but it also maintains the lowest level of 
biosolids. Alternative carbon sources, such as ethanol, 
tend to “gum up” the works. The major requirement for 
methanol is for removal of dissolved oxygen in the 
deaeration reactor, as oxygen levels are so much greater 
than perchlorate levels in the first stage of the process. For 
fire safety reasons, the methanol is dissolved in water 
(generally 50%). The rate of feed of methanol is so small 
that even if it were to exit unused, the concentration would 
not reach hazardous levels. 

It should be noted that while the bacteria involved in 
denitrification are hardy, best operations are realized when 
temperatures are controlled between limits of 8 °C and 35 
°C. During normal flow, the influent water maintains 
adequate temperature control. During startup, when 
recirculation is 100% care should be taken to turn on the 
circulation pump in the Hall reactor for a relatively small 
time period each day. 

The way the system works is that the bacteria can “eat" a 
constant rate of contaminant. Thus, the flow rate of water 
through the system isn’t a significant parameter in the 
design. The most significant system size factor, which 
determines the basic system size, is the total amount of 
material that is to be removed per day. This number is the 
product of the flow times the concentration. For example, 


for a system that will remediate 1000 gpm of water having 
a concentration of 10 ppm, the amount of contaminant to 
be removed is 120 pounds per day. For this example, 
EcoMat estimates that it can build, own and operate this 
system, at the currently demonstrated sizing criteria, at 
total cost to the customer of $.50 per thousand gallons. 


A.1.3 Operations 

The system was built on a skid that is four feet by four feet 
in size. Startup operations involve continuously recycling 
the water through the reactors while feeding methanol and 
assuring that there is adequate perchlorate in the water. 
This recirculation need not be constant, and in warm 
weather, when the bacteria might overheat, it is best to 
circulate for no more than a few hours per day. Periodic 
measurements are made of the dissolved oxygen levels 
leaving the de-aeration reactor. When the dissolved 
oxygen level is below 1.0 ppm the system can be opened 
in stages, until it is wide open. After start-up, operations 
remain continuous, and it is only necessary to check the 
system once daily to be sure that no spurious upset has 
taken place. The methanol source only needs to be 
replenished every few weeks. 

At this DOD site there were a number of upsets, 
particularly during the early operating days. First, someone 
driving by pulled the main power plug! A few days passed 
before the operators realized that there was something 


A-2 






























































wrong. During that time, the bacteria used up all of the 
oxygen and perchlorate and started producing hydrogen 
sulfide. The system turned black and smelled 
characteristically of that material. The system was re¬ 
started and within a few days it returned to normal 
operation. 

Importantly, Earth Tech (the contractor using EcoMat’s 
system at the site) was not concerned with optimizing the 
time for performing the remediation of the water from the 
Baker tanks. With a retention time of one half-hour, the 
remediation proceeded sufficiently rapidly. However, 
based upon EcoMat's denitrification experience, much 
shorter retention times may be feasible for perchlorate 
remediation, further reducing the cost of new systems. 
EcoMat is pursuing this possibility. 

A.1.4 Results 

Measurements were made by Earth Tech on a regular 
basis. As a result of the "closed loop” feature, it was 
possible to control the outlet so that only when the effluent 
perchlorate concentrations were below the allowable level 
(ND) would water be discharged to a cleaned water baker 
tank. Initial results during the startup period were as 
follows in Table A-1 (in micrograms per liter): 

A.1.5 Future Plans 

Reactors 15 times the size of the subject reactor are 
currently in operation, and EcoMat has designed reactors 
as large as 100 cubic meters. The reactors may be 
ganged together to provide adequate volume for any flow 
rate. EcoMat plans to offer its perchlorate remediation 
process to customers as a build-own-operate package, 


Table A-1 

DATE 

INLET 

OUTLET 

2/17 

350 

210 

2/18 

390 

160 

2/21 

390 

410 * 

3/06 

350 

ND 

3/07 

370 

ND 

3/08 

340 

9 

3/09 

320 

ND 

3/10 

320 

19 

3/15 

260 

24 ** 

3/23 

300 

ND 


* Power loss 

** New Tank. When the Baker tanks were emptied, the 
system was moved to another location at the DOD site, 
where it is presently in operation. 

with pricing in the range of $.50/1,000 gallons. 

A.1.6 Conclusions 

It appears to EcoMat that this system is one of the most 
inexpensive ways to remediate perchlorate from water. For 
very large systems it would be cost effective to implement 
on-line measurement capabilities with SCADA systems to 
transmit data to a remote operations center, facilitating 
satisfactory operations. 


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